If anyone has any thoughts, I'd be glad to hear them. Here is a partial ls -l of my Documents folder Last login: Mon Nov 25 16:02:27 on ~ % cd Documents % ls -l This let me access my files for the remainder of the day, but today - no access. So I deleted my existing user, created a brand new one, and copied the files from the clone to the new user account. I tested the files stored on a clone of my HD and found they were able to be opened. So I Reset Permissions again, and the same result happened, access for one day, and the following, no access. The following day the issue reappeared and I could no longer access the files. That actually gave me access to my files for exactly one day. I followed the steps outlined above including the steps in the 'Reset permissions' section on this page: Resolve issues caused by changing the permissions of items in your home folder. I did not notice for a couple of days until I tried to access an older. The files were originally transferred using Migration Assistant. It started when I migrated to a new iMac running 10.15.1. sudo: unable to open /var/lib/sudo/'My User Name'/0: Read-only file system W: Not using locking for read only lock file /var/lib/dpkg/lock E: Unable to write to /var/cache/apt/ E: The package lists or status file could not be parsed or opened. I have this problem with every file type in my Documents folder.

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