You may also notice that windows explorer also locks up when trying to work with the same .pst files, even when not using Outlook.

We’ve been seeing this a lot lately. Outlook 2010 on Windows 7, mostly x86, locks up completely when trying access .pst files that have been placed into re-directed My Documents folders. We used to do this a lot for folks back when we were running XP/2003, and although it was never officially supported by Microsoft, it worked out pretty well. After all who wants to lose locally stored archive files when a PC’s hard drive dies? Not me that’s for sure, which is why it makes sense to stick them out on a network share somewhere. Because email is private you don’t want to be sticking these files out where just anyone can grab them so we ended up just placing them into re-directed My Documents folders, the permissions were already in place and it just made sense. Flash forward, and now we’re upgrading PCs(well replacing actually) to Windows 7 and all of a sudden we’ve got lots of users unable to access their archive files.

The problem appears to be in Windows 7’s offline folders functionality. There are two solutions that we’ve come up with so far:

1) Disable offline folders for the affected PCs.

2) Move the .pst files to another share, and disable caching on that share. The only problem with this is when users are disconnected from the share they’ll get error messages in outlook saying that it can’t access the archive files.

I wish I had a better solution at this point but I don’t. I’ll update again if I can figure out a better way to solve this, feel free to throw your suggestions at me if you’ve got something that works and is more flexible.