Why might iChat not connect after upgrading to Lion?

Since upgrading to Lion, iChat refuses to connect to either my AIM or Google Talk accounts. (Not a Google Apps account, fwiw.) Interestingly, if I sign in to AIM on another computer and try to get iChat to sign on, I get a message that I'm trying to sign on in more than one place, but iChat still shows status as "offline" for all accounts.

So far, I've tried deleting all the com.apple.iChat preferences in Library, but to no avail.

Solution 1:

For some reason iChat defaulted to selecting "https only" on aim and gtalk for me. Once I deselected both https options, iChat accounts connected successfully.

Solution 2:

This happens to be occasionally, and I'm almost sure it's a bug in Lion. Disabling then reenabling my AIM account in the iChat preferences seems to temporarily fix the issue.

Solution 3:

Open "Console," located in your Utilities folder, and type "iChat" into the filter search box. Then open iChat and watch the console for error messages.

Solution 4:

Change the port to 443, with SSL enabled. Doing it worked for me.

Solution 5:

Try dropping your account and recreating it. That worked for me.