Presumably you've searched your sys, to include hidden files, for *.pst?
As you must have upgraded outlook, in this time, did you also create new
data files, both Archive and current, in the 2003/2007 format or are you
still using data files created pre 2003version?

You cannot really lose a file, completely from the sys, without some form of
user intervention. If it was deleted, there are recovery programs but they
work best if used ASAP after any deletion, as the continued use of a PC
likely means any residue of the file on the hd will have been overwritten

As with any data held on a PC, a data backup is allways wise.

"Arthur MacLeod" wrote in message
...
After ten years of letting Outlook manage archiving, I notice I have loast
all my archived email. I'm not sure when the last time was that I looked
up an old message, perhaps a half year ago. How do I go about recovering
lost data. The outlook pst would be on an external hard drive where it is
intact. The archive.pst would be on the default C: drive location where it
is empty. Would I be able to recove lost data, perhaps deleted, with a
utility. Where do I start?

Arthur
Vista-64, Office 2007, Dell Precision Platform