Error 87 while trying to delete a directory

As shown with the attached video, I get an error 87 while trying to delete a directory. DO version is 16.3 (stable).

Do you see the same error when doing the same thing in File Explorer?

The error is probably coming from the NAS, not Opus.

Please also update to the current version.

It was DO version 13.6. So that seems to be the newest version?

Unfortunately, I already deleted the directory on the NAS with its file explorer. Just wanted to inform you of a possible problem.