How Can I Check My iChat/Messages AIM Password ?
If you can not log on to the AIM server with iChat or Messages you may need to check your account name and password.
Checking the name is right is as simple as going to the iChat/Messages Preferences in the iChat/Messages menu and from there to the Accounts section.
Since the beginning of iChat, Apple issued ID such as ones ending in @mac.com have also been Valid AIM Screen Names.
Accounts names from @mac.com will need to be typed in full.
This also applies to @me.com ones linked to iCloud before June 2012 and @icloud.com ones after this.
However changes in the security or Messages and the AIM Server tend to mean they no longer work in iChat 1 through iChat 6.0
It is also true that in earlier iChat versions the Apple Links do not point to the iCloud servers to check the ID when adding an account.
AIM account/screen names do not need the suffix (@AIM.com or @aol.com).
At this point is is best to return to a web page to test the name and password work. (You may have mistyped it)
Start with the AIM Settings Page and see if you can Login.
This did work with Apple @mac.com names and Apple MobileMe issued @me.com name until June 2012 as well as AIM names.
iCloud Issued @me.com names will not work on this page.
AIM and Apple upgraded the security that allows AIM to check your Apple ID password against the iCloud/Apple ID servers.
There is now a Login to Apple and to AIM at the same time in the Messages app that provides confirmation your are active and allows the check on the servers.
As iChat 1 though 6.0 cannot do this check @mac.com @me.com and @icloud ending names will not work in iChat any longer
One common cause for not being able to Login is that the @mac.com and later registration pages have encouraged longer passwords than will work with the AIM servers. The AIM servers have a limit of 16 characters.
You will need to go to the iForgot site and change the password.
You can use an Email method or do it On line in a Web Browser. The second may be better if you no longer have access to the email you linked with the @mac.com name.
If you think your AIM Password needs changing go to this page to check your AIM name. This will cause you password to be emailed to you.
The Keychain holds all your Passwords. You can not check they are correct without opening Keychain Access.
You will probably need to look in Keychain Access to reset the password.
Open Key Chain Access (In Applications/Utilities)
1a) Top left select the Login item
1b) Bottom left select Passwords.
2) On the right find the Screen Name
3) Click on it. The rest of the details will fill in (except the password)
4) Put a tick in the "Show Password" box near the bottom
5) A window opens asking for your ADMIN password.
6) Type your ADMIN password in.
7) Hit the "Allow Once" Button.
7) The window should close and your password for your iChat account should appear in the last text field.
8) Correct as required. (Check carefully your spelling)
9) Close/Quit Keychain Access.
10) Try iChat again.
Apple Issued IDs no longer work in iChat versions 1 though 6.0
They will work in any version of Messages plus the last version of iChat 6 (6.1)
However AIM issued Screen Names can be checked by the AIM settings web page
If it is password length for an Apple ID this can be shortened At the Apple ID page
Hope this helps.
EDIT Date 9:14 pm Sunday; April 17, 2016
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb (Snow Leopard 10.6.8)
Mac OS X (10.6.8),
Couple of iPhones and an iPad