Cannot log into Windows Live Messenger after upgrading to Windows 7 Build 7057 - error code 8e5e0645 fix

If you perform an upgrade (instead of a clean install) to Windows 7 build 7057, and find yourself facing the error code of 8e5e0645, it can be fixed pretty easily.
Exit out of WLM and delete the %USERPROFILE%\AppData\Local\Microsoft\Windows Live Contacts folder. Simple enough, correct? Unfortunately, I found this out after uninstalling and reinstalling all the Live applications and deleting any WLM related directory in my profile. Little by little, it ended up getting narrowed down to that directory by itself.

For some reason, I've also noticed that Desktop.ini files seem to be sprinkled across the drive when I previously "banned" them from the local drive. A quick cd /D C:\ && del /s desktop.ini fixed that problem. Only do this if you don't care about desktop.ini files, post-upgrade.

Update: Looks like someone beat me to it, and had the same issue and blogged about it too, with regards to WLM. Ditto on the desktop.ini issue. Must be common.

As always, I recommend clean installs, but sometimes I try out the upgrade process to see what breaks.