Question: Outlook 2002 problems including the error message “The messaging interface has returned an unknown error. If the problem persists, restart Outlook”

Here are the multiple of problems that I experience with regard to my Outlook 2002.

•     When I try to move a mail message from one folder to another I get the error message: “Cant’ move the items”

•     When I try to delete a mail message I get the error message: “The messaging interface has returned an unknown error. If the problem persists, restart Outlook”

•     When I try to download messages the message flag (the envelope) that indicates down load flashes however nothing comes into the INBOX.

•     After the down loading has stopped I get the following error messages for all the mail boxes where there are messages waiting to be downloaded: Task ‘EMAIL ADDRESS’ - Sending and Receiving' reported error (0x8004060C) : 'Unknown Error 0x8004060C'

•     A message which is sitting in my outbox (addressed to myself as a test) is uploaded every time and use the send and receive function. However the message is not moved over to the sent folder after the upload and is therefore uploaded again the next time the “send and receive” function is performed.

This problem started 24 hours ago and is a completely new experience for me. I have not done any changes to Outlook prior to this problem occurring.

Answer: A good way to fix this problem is to delete old e-mails that you don't need anymore.  If you can't delete them and get an error message, use the shift key.

Shift-Delete will prevent messages from going into Trash can.  It will delete them from the pst file permanently.

Doing this fixed my problem.  When I try to delete a mail message I NO LONGER get the error message: “The messaging interface has returned an unknown error. If the problem persists, restart Outlook”.

The reason this happens is because the Outlook .PST file grew to be bigger than the 1.8GB limit that is set in the program. There is no way to make it bigger - you just have to clean out your mailbox more often.