As suggested on
Softpedia (via
Messenger Support) to clean up corrupt contacts cache, you can do the following. CCleaner may have already done this for you, but it's worth a try anyway.
quote:
1. Click on Start – Double click on My computer
2. Browse to the location:
(In Windows Vista, C:\Users\<Windows Logon name>\App Data\Local\Microsoft).
(In Windows XP, go to C:\Documents and Settings\<Windows logon name>\Local Settings\Application Data\Microsoft)
Note: Windows Logon name is the logon name that you use to sign in to windows. Your Messenger email address is the address that you use to sign in to Messenger.
3. Look for Windows Live Contacts folder and delete the entire folder.
Note: Please ensure to exit Messenger even from the task manager before deleting this folder.
4. Try to Sign into Windows Live Messenger again.
As a last resort, try
CookieRevised's guide to a complete clean install.
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