Need sync help with Outlook 2011

here is the history of this computer and email setup on this machine. the first computer was a work PC with MobileMe to sync mail and contacts with a home macbookpro. later the PC was replaced by an IMac.

i exported the .olm from the macbookpro (running Entourage 2008) and copied it to the IMac and imported it (Entourage 2008). we later upgraded to Office 2011 and i switched the database over to Outlook 2011.

now there seems to be a sync error and i get hundreds of these errors that say:
Could not synchronize record: Email Title to Exchange server: AccountName

followed by 1 of 2 different error codes:
19708 and 19760

how can i fix this?