My Outlook 2003 is in physical disk 'C:' (name 'WinXP') and its 'archive.pst' in physical disk 'G' (name 'Data').

Every Saturday I run backup TASKS --all PROGRAMS closed-- and COPY all data files sotred in 'Data' into external disk 'K'. It has gone fine for years.

Last Saturday I couldn't copy the 'archive.pst'. Whenever tried, I got the message "The process cannot access the file because another process has LOCKED a portion of the file".

This Saturday (today), same thing.

What 'other process' can it be if all programs are closed? How can I unlock the 'archive.pst' so that I can copy it somewhere else? A couple suggestions:

1. Start in Safe mode and try doing your backup.

2. In NORMAL mode, open Task Manager and see what processes are running. Kill one or more and try again. If it still won't work, pick one or more processes to kill and try again, and so on. This might lead to the culprit. Another approach here would be to run msconfig, select Startup, and unselect some processes, restart, and try your backup, and so on.