Win11 will not open previously recorded AUP3 files

Have a new Acer Aspire 5 running WIn-11 and using Audacity 3.1.3.
I moved my AUP3 (and older AUP) files onto the NTFS 1TB HDD. I know you cannot directly open from FAT or eFAT drives.
When I go to open any previous AUP3 files I get the error message “Cannot import AUP3 format. Use File>Open instead.” The files also will not open using the OPEN command. It will open (and covert) older AUP files. Also if I record a new AUP3 file, it will open that file after being saved.

I run the current Audacity on my Win8.1,WIn10, WIn 7 machines (also I use older version on Audacity on an XP machine that I use as a recording backup for my radio show). I have not had any issue transferring AUP3/AUP files between these machines.

Thoughts?
Thank you in advance - Audacity is a truly a workhorse - used by a couple of the smaller radio stations and their hosts for their shows.

Dr LAB

We’ve seen this error before, but not often. See: cannot import AUP3 format, Use file> open instead for some suggestions.

File>Open does not work either

OK; zip up an offending .aup3 file and upload it to your favorite file sharing service. Post (or PM me) a link; I’ll take a look at it.