Out of luck? No way! I wish I had this much luck with the big sweepstakes! Okay, let me explain.
I have a dual-boot Mac. I was on the Mac side when I saw your reply. I thank you for telling me about Outlook files not wanting to be copied when they're open, since in this situation, Outlook is open practically 100% of the time. So I'll just make sure that my daughter (this is all about her PC) closes it more often to give Carbonite a chance to work. One problem area resolved, but not the big one.
On Rendezvous (Mac's mail handler very similar to Outlook) I found File>Export, which would apparently generate a searchable file for selected (or all) mail items. Okay for the Mac, now let's switch to the Windows side. It also has some exporting facility, but very limited, one folder at a time, CSV files (one of the choices). Not what I need. But then ...
I noticed a beautiful gold-colored box in the navigation pane that said "All Mail Items". I selected that and went to the search in the upper-right screen and got the perfect solution with no effort. God bless the curiosity and persistence of an old programmer!
Now, as long as I don't have problems creating smaller data files and distributing existing mail among them, I should have it taken care of. Wish me luck.