Preview won't let me open pdf files I created a few years ago on a different mac computer
I upgraded to a 2022 Macbook Air, and am using Monterey 12.5.1.
I have some older PDF files created on an earlier macbook. I could not get Adobe to work on the new computer so I started using Preview. I cannot open anything but very recent pdf's with Preview. The message is "This document is password protected" and "please enter the password below", on the usual grey background for these things.
I never put a password on these files. I tried a couple of online unlock pdf password sites, no success, both said it was a very strong encryption.
Can anyone help me recover these files?
Thanks
-Lynn
MacBook, macOS 10.14