Outlook 2003 can't move the items. the set of folders could not be opened

[tome]

On a pretty much random basis, Outlook decides that a .pst file is being used by another program, and it won't open it.

Typically I can switch from one .pst to the next - until the 12th file - then it says "no". However, it will open some additional files, but not others. 12 seems to be a "magic" number.

Also, when I only have my inbox open, such as when I am moving e-mails into archive files, it will say that certain .pst files are unavailable. Yet, if I shut down Outlook and then restart, and select the errant .pst file, it opens just fine.
One error is
can't move the items. the set of folders could not be opened
I did detect & repair which did not resolve problem.

[jockmullin]

Wow, 12 pst files - I've never tried that and don't have so many so can't test here. However, some thoughts:

- are these PST files all local? PST files cannot reside on network shares.
- could it be antivirus/real time backup/encryption tasks jumping in and accessing the PST files? I have seen a similar problem when running WD Smartware live backup.
- are you possibly low on virtual memory or other resources preventing concurrent access to so many files?
- anything relevant in the event logs?

Jock

[tome]

Tried the things you suggested nothing in event files and increasing virtual memory did not help. Is bosses system thats why it took me so long to reply, He installed some updates ths other day and the problem seems to have gone away.