I just changed my NUC for a more powerful one and did a backup before putting the M2 Sata card in the new NUC. Installed ROCK ok went to restore the backup and I got the following messages see screen shot.
I found a functioning backup on my NAS drive, which is now restoring… Phew…
However it would still be useful to know why it wasn’t working from the other two locations
It looks like you’re missing your roon_backup_root file in the first screenshot, how have you transferred the backup to the USB drive in the first screeenshot?
The roon_backup_root file is sometimes hidden by operating systems so I would suggest making the backup directly to the drive by using Roon to point to it and not copying the backup over from another location just to make sure that all the files are properly saved.
Either way, glad to hear that the NAS drive backup worked ok.