I am using a new WD My “Passport for Mac” 2 TB, starting under macOS Catalina and now under Big Sur. It is used for TimeMachine backups. Since the beginning it happens about 2 or 3 days after last boot of my iMac that TimeMachine cannot start the backup as the TimeMachine folder was not found. Opening the disk in the Finder I don’t see any folder or file. Opening the disk in the Mac Terminal and listing its content with “ls” it also shows no folders nor files. Only a reboot of the Mac brings back its content.
This is the third disk of that type that shows this phenomenon. A second non-WD disk that I am using for such backups alternately behaves normal.
Why does this happen only on WD drives and what can I do to resolve the issue?