Lost my network and bought a new machine. AOL Desktop 10.x was the option I had to load. Finally got my files back from the old machine, but all the on-line instructions on how to load my filing ...
I can't help, other than to suggest that AOL 10 was hung out to dry many years back. It never took off - in fact folk hated it - so it was left unsupported and unpromoted.
AOL 10 uses a different email format and doesn't have a .pfc folder. You can import your mail from 9 to 10, but if you go back to 9, you can't reverse the process - not that it matters, as all your email is stored on AOL's servers and accessible via web mail using any browser you like.
AOL 10 offers nothing that IE or Firefox or Chrome etc offer - other than the AOL logo. But it is an inferior, old, obsolete browser.
I wouldn't go near it myself.
By all means continue to use AOL email. It's free and available to anyone, anywhere via any browser of your choice. You don't need use AOL software at all.