I've gotten this error before and usually by going in and changing the system to open with the correct email application and sometimes unreg'ing and re-reg'ing their msmapi32.ocx file helps. But it has come to my attention this doesn't help users running MSN mail as their default email application. Is there anyway to correct this for my user? They keep getting this error:
MAPI FAILURE: VALID SESSION ID DOES NOT EXIST.