Has MSN Live Messenger started crashing upon load up all of sudden for you? Since the last week of July 2010, Live Messenger hasn't worked on several PCs we use at PCSTATS, regardless of Windows XP or Windows Vista operating systems. Uninstalling and reinstalling Windows Live Messenger won't fix the crash issue, what you need to do is edit one registry setting to work around what is apparently a Microsoft bug. Tread lightly and make a back up of your registry if you're unsure.

Here's how to fix the July/August 2010 Windows Live Messenger crash issue:

Go to: Start > Run > type "regedit" and hit okay.
In the registry editor, navigate to: HKEY_CURRENT_USER/Software/Microsoft/MSNMessenger/PerPassportSettings

Within "PerPassportSettings" there will be multiple entries with numbers representing each MSN Live account you've logged in with. In each (or possibly only one), expand the numbered key and look for a string labeled "UTL" at the bottom of the page. Delete the value within "UTL" string by right clicking on it and selecting "Modify", then deleting the "Value Data." Do not simply delete the "UTL" string itself - just the data it contains.

After you've cleared the UTL value for each numerical entry representing different Passport accounts (if there is more than one), Windows Live Messenger will load up without crashing.

The UTL value contains various bits of XML data related to the MSN Messenger Live account. Apparently, in the past week there has been an issue resulting in "bad data" being stored in UTL string. This "bad data" causes Messenger to crash on startup. After clearing the UTL value, correct data will be restored the next time you log into your MSN Live Messenger account. This Tip comes via the smart folks of forums.NCIX.com!