The main reason you get that error message is that the install of Office was not updating the Mapi32.dll. Extract the MSMAPI32.DLL from the Outlook cab file from the install and rename it to MAPI32.dll. Backup the current MAPI32.dll in the system32 directory and then copy the new MAPI32.dll into the system32 directory.
This may happen for many reasons. The main reason is that you have another application installed that uses the MAPI subsystem, i.e. Blackberry Desktop Manager, Exchange System Manager, etc. The office install doesn't seem to replace the dll if there is an older version already there.