Windows live messenger doesn't remember sign in username and password

As my tradition to criticize bad software work, now it's yahoo messenger time.

not enough that they can't do an easy task to prevent entrance of bots to their chat, their chat is full with bots and very few real people.
now installing yahoo messenger or from what i read it's actually their toolbar, screws the windows live messenger. after i installed yahoo messenger, windows live didn't remember my login detail upon restarting.
even after i uninstalled yahoo. i found in another forum a solution written by:
Adam Johnson, on Aug 14, 2009 11:14:42 pm BST
[quote]
After hours of messing around with RegEdit + Yahoo Messenger + Microsoft's Virtual PC I've found the problem and a solution to why apps like Msn Messenger suddenly can't remember their passwords anymore.

When Yahoo toolbar gets installed it sets the following registry value:

[HKEY_USERS\S-1-5-21-796845957-926492609-725345543-1003\Soft­ware\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders]
AppData = %AppData%

The problem here is AppData should actually be the following

AppData = %USERPROFILE%\Application Data

So when MSN or other apps that use that registry key go to save their data it gets lost.

So the solution is simple, run regedit and go to

[HKEY_USERS\S-1-5-21-796845957-926492609-725345543-1003\Soft­ware\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders]

and set the value AppData to a data value of %USERPROFILE%\Application Data
[/quote]

http://en.kioskea.net/forum/affich-134602-messenger-does-not-remember-my-username