can't send mail, PST file is being accessed by another program

[GWW]

I have Outlook 2003 using Hotmail. No problem receiving mail, however when I
try to send I get the following message:

The file, C: \...\ Outlook1 PST is being used by another program and cannot
be accessed. Close the application and try again. There is nothing else
running. Using OneCare as antivirus.

 

[Gis Bun]

Try disabling OneCare's service(s) and see if you can send. Even though the
task manager says nothing else is running, there is plenty [although most not
associated with mail].

Also try rebooting the PC and then send. Sometimes an app doesn't let go of
memory.

If that fail, from the task manager kill processes [that you can], one by
one until you find the culprit.