From the summary:
If the directory used by the system to store MAPI dynamic profile information is unavailable for any reason, the synchronization service will not be able to log on. However, the console and logon test are able to successfully log on. The solution is to restore access to the profile directory or change the profile directory location via a registry key.
You can find this bulletin at:
Monday, February 14, 2011 12:32:00 PM