Cannot uncheck "do not backup" in security?

I use TM to back up my VM's. Except after the latest update, all the VM's have been marked as "Do not backup" in security settings. It stays checked, however.

To reproduce. Open VM settings. Go into security settings. Uncheck "do not backup". Close settings window. Close VM window. Reopen. Go into settings, it's checked again.

Ideas?

 

Deleted and recopied the files and now it works. Thinking it was some permission issue.