retrieve auto archived messages

My wife is using Vista. She needs to find a message from a few months ago--less than 6---that she thinks may have been automatically archived. I found the archive folder in C:\users\username\appdata\local\microsoft\outlook but I cannot open it. The extension is .pst (I'm not 100% sure of the path nor the extension). I can't find a program that will open the archive.

She has several other archive folders that she made herself--the message she needs is not in those.

Can anyone give me some ideas?

Thanks,
James

NOTE: This thread needs to be moved to MS Office.

Hi yashamax.
I would use the Vista Search function and do a search for .pst and see what it finds.
If you find the archive.pst or personal folders.pst you need to open them with Outlook 2000/Xp/2003/2007.
To do so try Opening Outlook then go to File > Open > .PST then browse to where the .pst file is, highlight the .pst file then click OK. Now you should see the archive on the left side of the Outlook window.
Raj