Luckily, most of my needed files are on my desktop. (Long story ... too long to explain.) I am unable to move files back to my internal hard drive after Big Sur upgrade. After typing "command I", only SYSTEM, WHEEL, EVERYONE are the offered choices in the Permissions Section. I tried to add ADMINISTRATOR - denied. I tried my name - denied.
I am not allowed to add myself for permission. Tried everything I know. Please advice!!! Thank you and God Bless.