About 2 weeks ago, my DSL modem started dying a slow, protracted, and painful death. Rather than fork over $80 to Earthlink, I went out to CompUSA and bought a noname modem for quite a bit less. Thanks go to BroadbandReport’s Earthlink DSL FAQ which revealed that I didn’t have to buy direct from Earthlink and pointed out the 0/35 VPI/VCI settings for whichever modem I bought.
Although the new DSL modem worked beautifully, I started having occasional connection problems with iChat AV. After googling turned up this helpful Apple support doc, I tried playing with my ports and firewall on the new modem–unfortunately without much success. After following all the port opening instructions from Apple, after opening all ports, after shutting down all firewalls, I still had connection issues.
Googling around brought me to this further Apple Support discussion which suggested I change my port from 5190 to 443. I opened logged out of AOL, opened iChat preferences, selected Accounts -> Server Settings and updated the login.oscar.aol.com port.
So far, so good but I’m still somewhat mystified as to why this fix seems to be working. Maybe the new port just plays nicer with the new modem. Any insights welcome.


One relatively uninformed guess: 443 is for HTTPS (secure HTTP), and your DSL modem may be configured to give a higher priority to traffic on HTTP ports than on other random ports (like 5190).
Glad to hear that it's working better now, though, regardless of the technical explanation :-)
Port 443 is the canonical port for secure HTTP connections. Network devices handle that port intelligently by default. The same workaround applies to Google Talk.
Well, unfortunately, I'm now getting new errors: "The server message was: Serv:RequestTimeout"
I am now living in a university campus in france with internet in the rooms. It is not a typical LAN with just ethernet ports in the rooms, we have dsl modems in each room (dont ask me why they choosed this setup). Well, all this to say that when i arrived here i couldnt mange to make iChat working with my aim account, only the jabber account worked and very unstable.
Changing to 443 made aim account work.
Thanks.
Hi Erica,
I have a similar problem with my Zyxel modem/router, which will only audio chat when I use port 443. I have no idea why and if I change the router everything works fine on 5190.
I think many of these cheap routers have cheap Stateful Packet Inspection firewalls that just don't "get" AIM at port 5190. Using 80 or 443 makes the router feel safer.
Any insights welcome.
Sounds like you saved what -- $50? -- and, despite having a high level of knowledge/expertise about such things, spent a few hours debugging the wierdnessees. And you're still not all the way home.
You've just described why virtualy none of your readers -- whose time is worth more than $10/hour -- should do anything like this little exercise.
So the insight: those of us who appreciate your wise postings, or at least your sharing, thank you, but this item per se is a simply a reminder that Gurudom is impossibly expensive for us. We should look for the simplest possible package and ignore your expeditions into craziness.
This is probably nothing not already known, but ...
Apple tech info article 106439 ("Well Known" TCP and UDP Ports Used By Apple Software Products) lists TCP ports 5060 AND 5190 as being needed for iChatAV. If you're using Gtalk's Jabber connection in addition to AIM, then you'll need to open up 5222 as well, and if you plan on using Bonjour to make iChat connections, you'll need to also open up ports 5297 and 5298.
As a last resort, if you want to make sure that it's a firewall problem in the router, disable the router firewall and see if the problem goes away.
I have a lot of problems connecting to Apple's iChat servers and I think they are related to my ISP. Thanks for this tip. I just tried it and was able to log in to my account immediately. Of course, I'll have to experiment with it more over time to see if it is a consistent fix.