My 1.9 GB .pst file for MS Outlook 2002 is not letting me download any more emails. It will also not let me delete any messages and I get the error. "The messaging interface has returned an unknown error. If the problem persists, restart Outlook." Restarting Outlook does not help as well as restarting the computer. I can send emails and that works, but receiving does not work. There aparently are 27 messages to download and it won't do it. I have already made a copy of the .pst file. Thanks in advance for any help you can provide.