I've just released Mp3tag v2.65a!
Discogs 401 Unauthorized
This version fixes an HTTP error stating "401 Unauthorized" when using the Discogs Web Source.
FYI, I've been busy with this for the last week and although using a different kind of word separator (URL encoded %20 instead of plus sign +) seems to work, there is no explanation for the error. I've started a discussion on the Discogs Forums and some of the staff are (maybe) looking into it.
You can download the new version from
Enjoy and be well!