Ralph Johns

iChat Information Pages

 


Error Messages in OS 10.4.7 and Above

This is going to be a long section. I have given a great deal of thought to whether to include it due to the complexity of trying to explain it.... But here goes....

In their usual manner of not actually saying they are aware of a problem, Apple have added a "Feature" to iChat at the 10.4.7 update that produces a Log file that can then be sent to Apple. It is specific to A/V chats.

Error Log Pop Up

What happens is the chat fails and a slide out window appears with a message about improving iChat with the info. There are two buttons at the bottom for Sending to Apple or not. Once the message is dealt with the pop-up disappears and you are left with just the Video Chat window (I say Video because that is where it is most reported) with the same message it always had. The actual message varies depending on the cause.

On the Log pop-up there is a "Details" reveal triangle as indicated in the picture above. Clicking on this will show you the actual log and the error code. You may have to drag it bigger and scroll to see all of it. They are made up of three parts - as coloured by me below.

Areas Covered

What I hope to cover here is somewhat twofold

  1. Is to show you what they look like and help people to look for information in the Logs that can help them fix their own problems.

  2. To widen the information that I and others have gleamed from previous iChat Error information shown in the Connection Doctor combined with the information in these Logs to a larger audience so that more people understand them.

Some History

iChat has always had moments of A/V chats that fail to Connect.

In earlier versions before iChat version 3.1.5 - which came with the OS 10.4.7 update to Tiger - the only place to instantly see any information any why this had happened was in the Connection Doctor.

The Connection Doctor is a window opened from the Video (Or Audio) menu in the iChat Menu Bar. In iChat 2 and 3 it has two views or Statistics and Errors.

The Statistic view shows the state of an active chat in Framerates, Bitrates or both Local and Buddy and two graphical bars of the incoming feed.

The Error view contains a History of Error messages that have happened during the current launch of iChat with Oldest at the top. (Four failed Chats will be four Messages). Prior to iChat 3.1.5 these did not list "Error -8" or whatever the relevant number is/was but just a brief Text Message. To some extent the same info is still shown there but is essentially a very brief synopsis of the Error Log.

The Error Logs greatly expand the info available but are not particularly end User friendly but with a bit of effort they can be interpreted as to how they relate to previous error info and what that means for iChat and the connection process.

I would say that the info on this page is based on many people's contributions on the Apple Discussion Forums regarding iChat over the last 4 years

What iChat is Doing During an A/V Invite

How iChat makes a A/V connection has a direct bearing on the type of Log seen and the Detail within it.

As mentioned on previous pages within this site iChat uses different Internet ports to do different functions. When you double click a Buddy's Video or Audio icon in the Buddy List, iChat sends an Invite on port 5678 which causes a Pop up Invite accept window to appear at the Buddy's end.

iChat will actually presume that they will accept and start the SIP (Session Initiation Protocol) part of the Invite which happens behind the scenes. (Port 5060 in iChat 2 & 3 and Port 16402 in ichat 4)The Logs we are talking about here are about how that SIP Invite has got along and why iChat thinks it has failed.

There can of course be several reasons and there are in fact 5 regular Error code numbers in iChat 3 and a 6th regarding iChat 4. The reasons stem from iChat's view of whether it is a local issue such as problems with the camera or video feed, though Connection speed problems (Are we ready to do this ? Can we do this ?) to issues with the Connection to the Internet and Buddy (see below)

SIP is a text based process that is akin to making a telephone call:-
Pick up phone
Dialling
Ringing
Answering
Chatting
Saying goodbye

The process works with iChat querying or telling an SIP server:-
Did they get the Invite ?
Do you acknowledge we are trying ?
Is it Ringing ?
Have they answered ?
Are we ready to Chat ?
Chatting
We have said GoodBye.

A Short Example of the Basic Error Log

Whatever the Error log number is and there are several it will contain this basic information. The red section is a series of Titles that in other logs tend to get lost with the amount of info shown . This means that the red section is normally a lot longer containing what look like repeats of the same information.

Date/Time:      2006-07-05 21:11:03.403 +0100
OS Version:     10.4.7 (Build 8J135)
Report Version: 4

iChat Connection Log:
AVChat started with ID 485234091.
[Edit Name]: State change from AVChatNoState to AVChatStateWaiting.
0x157a780: State change from AVChatNoState to AVChatStateInvited.
0x157a780: State change from AVChatStateInvited to AVChatStateConnecting.
[Edit Name]: State change from AVChatStateWaiting to AVChatStateConnecting.
[Edit Name]: State change from AVChatStateConnecting to AVChatStateEnded.
Chat ended with error -8
0x157a780: State change from AVChatStateConnecting to AVChatStateEnded.
Chat ended with error -8

Video Conference Error Report:


Video Conference Support Report:


Video Conference User Report


Binary Images Description for "iChat":
0x1000 - 0x170fff com.apple.iChat 3.1.5 (436) /Applications/
iChat.app/Contents/MacOS/iChat
[EDIT]

 ... At this point, " Binary Images Description for "iChat" ", the log goes on with all the bits loaded into action currently running the OS and iChat.

As you can see this one ends in Error -8 ( Chat ended with error -8 )

The above Log was also a failure where nothing but the Visible invite got through, so just the titles got listed. This will depend on the statements in the green section above.

A chat that connects but then Fails (normally Error -7) will show a line that reads [Edit Name]: State change from AVChatStateConnecting to AVChatStateConnected. It is not uncommon for incoming chats to show this line.

It is the bits contained between the titles (the Red Bit above) that is important in solving an issue.


Video Conference Error Report:


Video Conference Support Report:


Video Conference User Report:

Often the Log report will show much more in each title area. See below.

A Bit about How and What

What iChat Checks

Ok so you start a A/V chat. What is iChat doing.

In relation to the Error Logs it checks if it can get Video from the camera.

Next it checks if it thinks the Bandwidth and Connection speed to the Internet is good enough.

Then it checks that iChat got an answer from the SIP server that the A/V chat is in progress. This includes checking the Chat was Accepted in the Visible Invite part. In fact you will not get a Log if they don't. There will be a message on the Chat window to say they Declined or Refused.

This is followed by getting confirmation that the SIP part has started. This in turn has several sub parts:-

  1. The next bit is the SIP part confirms what ports it is trying to tell the other end it is using, with a "Trying Message"
  2. That is followed by a "Ringing" message.
  3. An Acknowledgement that the call is accepted comes next.
  4. Part of the next bit is the next bit is the Messaging part that confirms what sort of data is going to be passed next.
  5. When this Messaging bit is complete the Chat is connected and you and your Buddy can see and talk to each other.

The Different Error code numbers relate to failures at different points within this although some relate to connections that iChat thinks were not ended with a proper Goodbye during the chat.

What That Means in Error Codes

All chats will have an Error Message that is repeated on the Chat window once to Log is dealt with and forms the title to the Error info in the Connection Doctor that goes with it.

iChat will report an Error -22 if it thinks the Bandwidth or Connection speed it can see is not good enough.

Error -21 can be reported for checks near the beginning of the process or at the end. It can have different messages on the Chat window such as "Can't get Video from Camera". Most likely you can not see yourself in Preview while waiting for the connection. There are others but they are less common.

Error -20 seems to display the same messages. The deciding factor seems to be how far the process has progressed. In this case you will get the Preview pic but at the last minute iChat seems to say "I had video feed but now I don't"

There is of course one Error code number that is more common than the other and that is Error -8 It covers everything about the SIP part or the process. It is the detail of the Log that gives clues as to where the problem lies.

One Error can be reported at any time in a Chat that has been fully connected. This is Error -7. Actually Fully connected may not mean you see or even hear your Buddy depending on what causes the issue. What it means is the Chat ended without one end closing the Window to end the chat with the red button. Error -7 means the Connection process worked and the problem is elsewhere.

Error -4 is a report that something is wrong at the Buddy's end. They are always on Leopard but can be seen in iChat 3.

A Table View.

There are four/five common error code numbers and these relate to the actual message on the failed Video Chat window.

Error Number Message on Chat Window Cause and Solution
Error -8 (User) Did not Respond Generally a Port Problem somewhere. Can be a NAT related issue.
Check the middle part of the Log for port Numbers (See below). This will tell you if the ports are the "Right" ones. Use Page 3 and Page 4 to help. Try to avoid NAT if you can.
Error -22 Not Enough Bandwidth Generally this is caused by iChat being capped somewhere as to the Internet speed it has or can see.
Check the Quicktime setting first. Then the Bandwidth Limit in iChat. Test the Internet speed you are getting.
Error-7 No Data Received for 10 Secs

Anything that ends the call other than the Red close button. During a chat the Buddy's Pic will get "Frozen"
Make sure you are still on line and restart the call.
If it happening at the beginning of the chat and you do not see or hear your Buddy, look to Protection features of the Modem and Disable DOS or SPI features.

Error -20/21 Can not Get Video From Camera (Or other message) Despite what it says this generally is a catchall for chats failing at resource checks at start or end of the connection process. If late in the process, you get the sound you have allocated for A/V Connection and the change to the Picture-in-Picture Video chat window but then nothing. It normally points to not enough Bandwidth just at the point of Connection
Treat it as a Bandwidth Problem. Check that other apps or computers are not using up your Bandwidth. Some are caused by starting a download or Mail asking for new mail from the servers. Basically your Processor maybe suddenly busy. See Also this Apple Discussions Thread
Error -4 Remote IP Invalid This is seen at the receiving end of a Leopard Buddy who has a problem. The issues is that their iChat can see two or More network Options
This may be because they have a WiFi AND an Ethernet connection, a MIMO device or have Internet Sharing turned On in System Preferences > Sharing or are running the application Parallels.


So What's Next ?

How to Read the Logs

As I said above, you need to be able to check the log to some extent. They are full of data that probably means lots to a software engineer or an iChat guy or girl at Apple. I am going to show you here what I can make out of them.

If you have problems that this page can't answer then post on the Apple Discussion Pages in iChat 3.

Console And iChat

The Logs are also saved on your computer and can viewed in Console. Console is in Applications/Utilities. When it is open, click on the Logs icon top left. Use the reveal triangle on ~/Library/Logs (these are the ones for the current Mac User logged on the Mac). You will find another reveal triangle at iChatConnectionErrors. Use that to review your Logs for iChat. (or go to the same place on your Hard Drive and Home Folder ~/Library/Logs/iChatConnectionErrors change the view to list then select the youngest one for the last Connection Failure)

First about what is going to be useful from the log.

  1. The Error code
  2. Some or all of the next part of the Log that starts "Video Conference Error Report:"
  3. I some cases the first few lines of the Binary Images, like the edited example above. What we need to know is if there are iChat Add-Ons rather than all the info.

Example

A small sample of a middle section. Essentially there are two parts. The Title (Video Conference Error Report:) down to Content-Length: 507 and the bit with Audio and Video ports and Bandwidth Detection listed.
Video Conference Error Report:
3.324349 @:0 type=4 (00000000/22)
[VC_SIP_INVITE_ERROR]
[19]
3.324228 @SIP/SIP.c:2437 type=4 (900A0015/22)
[SIPConnectIPPort failed]
[]


Video Conference Support Report:
2.824908 @SIP/Transport.c:1218 type=1 (00000000/0)
[INVITE sip:user@u0en1.1 SIP/2.0
Via: SIP/2.0/UDP 192.168.1.100;branch=z9hG4bK567eedca227e0a8e
Max-Forwards: 70
To: "u0" <sip:user@u0en1.1>
From: "Name here" <sip:user@192.168.1.100>;tag=174545644
Call-ID: d2f87adc-0b95-11db-9fe2-9d41aeb913c4@lip
CSeq: 1 INVITE
Contact: <sip:user@192.168.1.100>;isfocus
User-Agent: Viceroy 1.2
Content-Type: application/sdp
Content-Length: 507

v=0 o=Ralph 0 0 IN IP4 192.168.1.100 s=name here c=IN IP4 192.168.1.100 b=AS:2147483647 t=0 0 a=hwi:34:2:999 a=bandwidthDetection:YES a=iChatEncryption:NO m=audio 16386 RTP/AVP 12 3 0 a=rtcp:16387 a=rtpmap:3 GSM/8000 a=rtpmap:0 PCMU/8000 a=rtpID:-1574383262 m=video 16384 RTP/AVP 126 34 a=rtcp:16385 a=rtpmap:126 X-H264 a=fmtp:34 imagesize 1 rules 30:352:288 a=framerate:15 a=RTCP:AUDIO 16387 VIDEO 16385 a=pogo a=fmtp:126 imagesize 0 rules 15:160:120:160:120 a=rtpID:-1178528325 ] [] 1.824612 @SIP/Transport.c:1218 type=1 (00000000/0) [INVITE sip:user@u0en1.1 SIP/2.0 Via: SIP/2.0/UDP 192.168.1.100;branch=z9hG4bK567eedca227e0a8e Max-Forwards: 70 To: "u0" <sip:user@u0en1.1> From: "name here" <sip:user@192.168.1.100>;tag=174545644 Call-ID: d2f87adc-0b95-11db-9fe2-9d41aeb913c4@lip CSeq: 1 INVITE Contact: <sip:user@192.168.1.100>;isfocus User-Agent: Viceroy 1.2 Content-Type: application/sdp Content-Length: 507 EDITED Repeats below until Video Conference User Report: (Which was empty in this case)

It has been edited as to User names and repeats of information where iChat tries multiple times to connect.


The Individual Lines

From: "Name here" <sip:user@192.168.1.100>
This bit shows you that you should be able to see your iChat name (screen name) and the IP where you are currently situated. It can be handy to identify if you have two DHCP servers on your network if the IP listed here is not the same as on your Mac.

The "To:" and "From:" lines contain different info if it is an incoming call. Depending how far it got it will identify your Buddy as well as you. Such as
To: u0 <sip:user@192.168.11.2:16402>;tag=506858487

To: "u0" <sip:user@rip:16402>
From: "0" <sip:user@lip:16402>;tag=486167384
Call-ID: b9ef4fb2-c60f-11dc-8444-fabe14394012@lip
CSeq: 1 INVITE
Contact: <sip:user@lip:16402>;isfocus

This is not strictly single lines but has closely related info. lip is Local IP (You). rip is Remote IP (Your Buddy). Contact: <sip:user@lip:16402>;isfocus is the person doing the Inviting detailed in that line as in this @lip is an Outgoing call and an @rip reference would be an incoming call.

tag=486167384
This is the SIP server giving the lip in this case an individual number. The Call ID line that follows is a mixed up reference to the (your) IP and the tag number.

a=RTCP:AUDIO 16387 VIDEO 16385 In Leopard this will show port 16402 for both.
This line shows you the ports that iChat is asking the other end to send Audio and Video data to you on. If other port numbers come up it means that there is a NAT related problem somewhere. This tends to mean that there are two connection devices at one end and both are using a NAT based Port opening method such as Port Forwarding, triggering or DMZ on both. Try without a router (i.e. just the modem) at one end to eliminate this as a cause. Adjust you network accordingly. It is worth noting that some ISPs NAT the service to the end user. In some cases iChat counts this as one occasion of NAT.

m=audio 16386 RTP/AVP 12 3 0 and
m=video 16384 RTP/AVP 126 34 See Leopard info above

The "m" value can be seen twice. Once for Audio and then again for Video. These should label the out-going ports. Again they should be from the iChat group of twenty (16384-16403). Normally they will be at the lower end of the group and between these two lines and the "a" line above you should have all 4 ports that are being requested. Again ports not in the iChat range either means you have a double NAT situation at one end or someone has not got the group of twenty ports open.

From these last two paragraphs iChat 2 & 3 should list a total of 4 ports (From the Group of twenty) whereas iChat 4 will list just one port at all 4 places, normally port 16402, but can be from a reduced group of 10 ports (16393-16402) and will always start at the top one.

CSeq: 1 INVITE And changes that are not in the Example.

This line indicates where the chat Invite Process is up to. This line changes or should change as the call is more successful. If it is stuck at Invite at every repeat you have the SIP Invite is not getting through. When it changes the line

Via: SIP/2.0/UDP 192.168.1.100;..... should also change to list the SIP text message and number part such as , [SIP/2.0 180 Ringing and [SIP/2.0 200 OK. At the Ok part the Invite line should read CSeq: 1 ACK for acknowledged.
From there the line that now has ACK will change to SUBSCRIBE and then MESSAGE.

The Log may show you this bit
<c-i v="0" st="f" en="sip:user@lip:16402">
<u u="-" x="-1" n="0"><s>c</s><h>i</h><m t="a"/><m t="v"/></u>
<u u="-" x="0" n="u0"><s>c</s><h>o</h><m t="a"/><m t="v"/></u>
</c-i>

As far as I can work out from where it comes in a Log and how seldom it appears, this section seems to be the bit where iChat confirms the Video and Audio Ports just prior to actual pictures being sent. It is more of an indicator of when and where the Process failed rather than being a readable part.

A much longer Log with comments added as an alternative to this style can be found here on page 14

OK. A quick review of what we have so far.

We have new Logs in iChat failed chats with the 10.4.7 update.
These Logs can be opened up and read as they occur or in Console or from the Users Home Folder/Library/Logs/iChatConnectionErrors which will open in Console when Clicked.
The error code number has a direct correlation to the message on the failed Video chat window.
There are several Error Code numbers, but the 5 listed here are the most common.
The logs can be studied for specific bits of data that can help point to the problem.

Stages For Each Failure Point.

  1. No Invite seen means the port 5678 is not open somewhere. It also means there will be no Log to compare to this page.

  2. Invite accepted and then failed chat with an Error -8 log -like the one higher up, with only titles, - tends to mean that the SIP port is (port 5060 in pre iChat 4 and 16402 in iChat 4) is not open somewhere.
    This could, as with most Logs, be at either end. With port 5060 for iChat 2 & 3
    It can also mean that port 5060 is either in use by some VoIP hardware or the ISP blocks it to try and get you to pay more for their own VoIP service.

  3. Invited accepted and a log with more data points to a failure after iChat has reached port 5060. At this point it is using a third party server called "SNATMAP" to negotiate which ports are going to be used. If you can see ports listed in the log you can be sure that you have got to this stage. It now a question of putting the info in the logs into context with the other factors on how iChat works.

  4. As I indicated above, sometimes your Buddy or at least his IP is listed in the 'To" spot. Along with his IP. It should be the SIP port they are using. Certain things can be gleaned from that. If it says 5060 then they are using iChat 3 or earlier. Port 16402 means they are on Leopard. Port 5061 tends to be AIM on a PC. Anything else can mean the issue is at their end.

  5. If, in the repeats, there are changes in the ports in the "a" and "m" values during the repeated attempts on longer logs, then it points to there being a NAT issue. This is where one end has two connection devices, modem and separate router, with each one using a method that uses NAT as part of the process (Port Forwarding, Port Triggering or DMZ). Basically each device that does NAT add address information to the data packet. When there are two NAT devices at one end - for some reason the port numbers in this address data seem to get changed. As a consequence this makes the chat fail as it is sending to the "Wrong" ports. As in this Example:-
a=bandwidthDetection:YES
a=iChatEncryption:NO
m=audio 16317 RTP/AVP 12
a=rtcp:16318
a=rtpID:552219969
m=video 16315 RTP/AVP 126
a=rtcp:16316
a=rtpmap:126 X-H264
a=RTCP:AUDIO 16318 VIDEO 16316
These are moved only slightly outside of the iChat range but it is enough. I have seen them much higher and lower on occasions like this one.
m=audio 29903 RTP/AVP 12 3 0
a=rtcp:29904
a=rtpmap:3 GSM/8000
a=rtpmap:0 PCMU/8000
a=rtpID:360478971
m=video 29901 RTP/AVP 126 34
a=rtcp:29902
a=rtpmap:126 X-H264
a=fmtp:34 imagesize 1 rules 30:352:288
a=framerate:15
a=RTCP:AUDIO 29904 VIDEO 29902

Here the ports have moves even further. I have seen no logic that I can fathom as to which way the ports will move.

It is worth saying though, that if you are trying to a PC and the ports are in the range 1024-5000 the problem with that chat is more likely to be at your end and less likely to do with ports. This is because iChat will tell AIM where it wants the data to come and AIM on a PC will oblige. If the ports are not set at your end, AIM will not change from it's default range.

  1. The Log shows an SIP port for the Buddy which is an iChat one and the ports are not changed but iChat never gets past the CSeq: 1 Invite Stage
    This can be a little deeper. If you are calling a Buddy get them to Call you. If this works then their Modem/Router or Mac Firewall is not allowing the Data for iChat to pass (some sort of Firewall or Port issue at their end as outgoing stuff tends to be allowed.)
    Also check what Error number they have at their End - If Error 7 it will be a Block caused by a DOS or SPI feature on their router or modem.

  2. You get Trying and Ringing but no ACK
    Most likely this is something to do with speed. It could be their processor is struggling but more likely it is Internet Speed or Bandwidth. Get your Buddy to check their Quicktime and iChat Bandwidth Setting (particularly if they are on Comcast or Road Runner)

  3. The "Algebra" bit is not present.
    Essentially this will be an issues about the SIP port. You may see repeats of the INVITE stage again with some port changes. iChat will try the INVITE again using different ports if it can not get a response on the first choice. Check for VoIP adapters or SIP/VoIP phones.
    Check how the ports are opened particularly if you or you buddy has routing modem as well as a router.

  4. The PING reference is missing
    Most likely this is a Blocking feature in your Modem or router to Pings from the Internet. Change the setting in your device.

Ok. That is essentially it for Error -8. It is by no means the complete answer but these are the most common issues.
Remember Error-8 is about the SIP Invite getting through your Mac Firewall, the router, the Modem, the Internet and whatever devices your Buddy has and his Mac Firewall. It is absolutely critical that the LAN is set up properly. A fairly Ad-hoc set up will work for a Web Browser because of how the ports fro that are opened in a modem or router but will not work for iChat. iChat has to "know" where it is in relation to other devices on your LAN and the Internet. It can not deal with appearing to be in two networks either created by using WiFi and Ethernet together or two routing device both giving out IP addresses.

Other Error Code Numbers

Error -22
With this error code the info in the first titled section Video Conference Error Report: tends to show repeats at first glance. Closer inspection shows it going through the SIP stages. You will get things that look like [SIP/2.0 100 Trying or [SIP/2.0 100 Ringing. As SIP is a text based protocol that basically follows all the steps in making a phone call you will also see "ACK" for acknowledged. Because of the Low Bandwidth it is the other comments after this that you will not see. If your connection speed (In this ichat has a minimum between 50kbps and 100kbps) is around the minimum and is closer to the 100kbps you may see the "Ringing" and "Trying" several times in the log. The solution as documented above is to check all things that have anything to do with the Connection Speed/Bandwidth.

Error -7
With this error log you are not going to get anything new. The connection was made and failed for some reason after that. Effectively this is a Log of a successful connection even if the chat wasn't. To be more specific, the other end may in fact get Error -20 "No Data received for 10 Secs". The issue is then on the Error -7 end. Most likely it is a DOS or SPI feature in a Modem that thinks the amount of iChat data is an Attack and cuts the Internet connection on that one port. Turning off such a feature will cure the issue.

Error - 20 or 21
With this error the Logs again are not that helpful. The error is effectively a lack of Bandwidth at the moment the Chat gets connected. It means at the start of iChat that it could "see" or rather read from the Quicktime data that there was enough Bandwidth/Connection speed and no capping imposed by iChat's Bandwidth Limit. See Page 4 in Quicktime and Bandwidth. What the error message means is iChat is saying "Sorry Boss. I thought I could get there." and is falling short. Due to the catchall nature of the Video chat window message that goes with this error you are going to have to check everything and the Log in this instance is of little use.

In addition with this Error number the actual message that is shown on the Video chat window when the log is cleared out of the way (or shown in the Connection Doctor) tends to change.
"Cannot get Video from Camera" really tends to mean that their is a resource issue on your Mac - the processor suddenly got busy - Mail downloaded new mail - a USB item was added when using a USB camera - a download effecting Bandwidth - another computer doing similar are the most common.
"No Data received for 10 Secs" means the actual call was connected although it may also have ended before you saw a Picture or heard your Buddy. It can occur at any time during a chat. Effectively it means you Buddy did not say "goodbye" properly with an SIP "Bye" stage. As losing an Internet Connection can cause this you or rather your Buddy has to look to Modem features that do the same thing (See Error -7 above)

Note It is possible to get the "No Data ..." Message in an Audio only chat if both parties happen to Mute their Mics at the same time.

Error - 4
This is seen on both Leopard and Tiger computers but it is a direct reference to the Buddy's end who will always be using Leopard and iChat 4.
It is accompanied by a message "Remote IP Invalid". This refers to the LAN that the Buddy has set up. It means that their IChat can "see" two networks. This includes being connected to a routing modem and router both doing DHCP so they get two IP address - using Wifi and Ethernet at the same time - using the Application Parallels and sharing the Internet connection with the Windows Install - Having Internet Sharing turned On is System Preferences > Sharing - certain MIMO Modem or routers that subdivide the WiFi signal get seen as multiple Networks.
Basically they have to sort out their LAN.
This issue is not reported in iChat 3. It tends to get hidden in Error -8 Logs instead.

Another View

Consider what you can do with iChat. You can use the same Screen Name to Log in to the AIM server twice (either two computers or two AIM clients /applications on the same computer). You can then text chat to a Buddy (or even in a Group Chats) and depending which version of iChat you are using you will see the text from the other computer or application duplicated on the Chat window of the other. At one time - and it may be still possible in iChat 2 - you could actually text chat to "yourself" such as at work and at home without anyone else involved. What you can not do is Video Chat with the same Screen Name to that Screen Name.

So in a Text chat it is possible to get the Screen Name logged on at two IPs (even if only on a LAN) and they can "Chat" to each other. However for Video and Audio Only chatting iChat can only have one IP and between tow Buddies that route also has to be unique.

In the case of an iChat 4 person having a Non unique route or IP the other end will show up Error -4 "Remote IP Invalid". For iChat 3 and earlier you will have to check what IPs are showing in the LOG but t still may not be obvious

If you have worked through checks when you have had an error log don't presume that the next one you get refers to the same problem. Just because it says Error -8 in the Log again does not always mean that the issue is the same as Error -8 covers so many variables within a LAN set up. Also getting another error log without checking the number will not tell you that you have solved one but had another issue as well. This is caused by the hierarchy of the Error numbers. For instance, Quicktime (Error -22/Not Enough Bandwidth) faults are seen later than Error -8 (User Did not Respond) ones and are effectively hidden until the first is sorted.

If you are going to post on the iChat Discussions at Apple then please post the Log with only the green, all the red and the amount of blue coloured text shown in my example above.

The Summary


I have tried to explain this two ways on this page and on page 14. I am sure I could find at least two more ways and I am not sure any really convey the full impact of what the Logs can tell you in just one go. At first glance they are a nonsense and it has taken me about a year or so to get to this point.

The concept I hope you have grasped is that an iChat Log is not a stand-alone thing. It is much more like the complete info a Doctor would need to come to a reasonable diagnosis. It is about the LAN, Mac and iChat setup situation as much as it is about the Log itself.

To digress with the Doctor thing a bit further; imagine you ring and tell your Doctor you are tired and lethargic and want to know what is wrong. If you miss out that you are on a Polar expedition running behind schedule, or live in a Malaria area or are Anorexic or that Thyroid problems run in the family, they are not going to have enough info to go on.

The Log does give you that more hands-on approach so that several options are excluded before you start. It also gives you a starting point to ask other questions about your LAN or your Buddies LAN and the set ups involved.

There is a format I tend to adopt with looking at these things.

  1. What is the Message on the Chat window that goes with this ?
  2. Do these "match" ?
  3. Are my Logs always the same no matter which Buddy ? (Is it Me ?)
  4. Does it list more (meaningful Info) than the Titles ?
  5. What can the Buddy tell me about their situation, LAN and Set up they have done ?
  6. What ports are listed in the second "paragraph" ?
  7. Are these what I expect and do they relate to iChat (or AIM on a PC) ?
  8. In the longer bit with the "m=" and port listings, do they agree with the paragraph that precedes it ?
  9. Does it Show "Trying", "Ringing" and "ACK" ?
  10. Does it show any "NOTIFY" or "SUBSCRIBE" ?
  11. Does the PING show up ?
  12. Is the "Algebra" bit there ?
  13. Has it got to the bit where it displays the Buddy's name in any form or their IP(s)
  14. Can the Buddy confirm these ?
  15. Are there excessive repeats of the same info ?
  16. Does it show the Bandwidth Check ?
  17. Are the Percentages "Good Enough" ?
  18. If a figure is quoted is it a valid speed for the type of Chat involved ?
  19. Is there a single line like the NoResource comment on page 14 that offers clues ?
  20. Is it time for a second pair of eyes and Posting on the Apple Discussions ?

Information Block

This site is about iChat from Version 1 through to iChat 4.x.x

It has a mixture of basic info and problem solving help.

The setions below will change for Specifics about info on the page on view

If you find these pages helpful please Donate to help keep them up to date

Compatibility

Confirmed to work with Win/IE 5.5 and later (should work in 5.0, but not confirmed), Firefox 2, Safari 3, Opera 9, iCab 3.02 and later, Mac/IE 5, Netscape 6 and later

Old browsers (IE version 4 or earlier, Netscape 4 or earlier) should only see a text-based page which, while not the prettiest option, is still entirely usable.

About This Page

This page attempts to tell you about how to look at the Error Logs that appear on Failed A/V chats from iChat 3.1.5 (Os 10.4.7) onwards

It details what we had before this point and how that also informed the way we identify what the logs mean about previous issues in the section called Some History and the panel alongside "About What that Means"

I have then included a short example. It is in fact almost everything except the "Binary Images of iChat" part. It is colour coded to highlight the three fundamental parts of a Log.

The next section has an overall title of "A Bit of How and What". The two panels underneath this look at how iChat runs through the Connection Process after the Visible part of the Invite and What that means in terms of Error Number codes.

Some of this information along with some Ideas of resolving the particular Error Log Number is then presented in a table form

The next step is obviously then what you have to do to Read the logs, where to find them and has a picture of one as it will open in Console.

At this point I have included an Longer Example minus the header info. In fact it is just the two "Paragraphs" that inform you about the INVITE part.

I then have a section I have called Individual Lines where I try to explain what specific lines are telling you. This ends with a Link to Page 14 that has a much lon Log with comments as it goes along as another way of explaining things.

A review is then included of where we are up to.

Hopefully by now you will have gathered that Error Log numbers have a correlation with how far the connection process has got. These points or Stages are then highlighted again concentrating on Error -8 mostly.

Specifics about the other Error Log Numbers have a panel of their own. This includes linking the messages seen on the Chat window or in the Connection Doctor with the actual Failure Log number as a reminder about the direct correlation.

And of course there is a Summary which has a 20 point check list on this subject.