Cover Art for Movie Files

I am no longer able to drag cover art files onto my movie files using this program. Is this a settings issue?

"Movies" is a very general term. Could you please specify with which file type you have problems?

MP4 movie files. I cannot drag and drop cover art onto the appropriate space to attach cover art for that movie file. It worked up until three weeks ago.

Then see if you can still modify the files from 3 weeks ago and only the new ones do not behave. It could be that some mp4s do not allow modifications and have to be re-ripped.

That sounds like a reasonable approach to this. Thanks for your feedback.