Hi All,
This may depend on whether you have entered and Apple ID that ends with either @mac.com or @me.com and the Password length that has _ AND _ try and talk to a AIM Buddy.
Messages asks for an Apple ID as you set it up.
At this point it is a little like FaceTime in that it uses a Name rather than a Number.
From here you cac "Call" anyone in your Address Book that has an iPhone/iPad number, using the Blue + sign top right and the Contacts list.
At the same time Messages will uses all the iChat Info you had an launch the Buddy Lists you had.
An AIM Buddy List can only have a max of 16 characters to a Password. The aforementioned Apple ID s are also Valid AIM Names but will only work if the password is not too long.
Clicking on a Buddy will open any Saved Messages you had with that Buddy (Going back to the earliest saved) and place them in the Messages window using the tabbed Chat method from iChat 4 (although it now includes the Buddy iCon/Address Book Pic and the "tab" is therefore bigger).
The Messages window becomes the place where Text Chats take place.
These Text chats can be iMessages to Phones/iPads with cell coverage or Touches.
They can be good old IMs to iChat Buddies
SO....
Your Apple ID may have worked to Sign-in if the Password is over 16 characters.
However if you use that same ID and try to contact someone in the AIM Buddy list it will not work as AIM have a 16 character limit.
You can Change the "To:-" and the "From:-" by clicking the Contact's/Buddy's name.
It has always been a problem that the various Apple registration pages have said @mac.com names and MobileMe (or iCloud) @me.com names are valid AIM screen Names but have not pinted out the Password needs to be kept to no more than 16 characters.
Messages provides a cross over point that may cause problems with different logins that use the Same ID
8:38 PM Friday; February 17, 2012
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