trying to use a batch process to remove metadata from all my mp4 videos.

Sorry for not using your native language.

Metadata++ looks remarkable and I could see it very useful for my photography hobby.

The problem I'm trying to solve right now is with my media centre database. My media collection is large and to keep it organized for my servers it puts each video file in a folder with several other required files (pictures, subtitles, notes etc.).

What I would like to do is:
Select a folder to run the batch process in.
Have look in all the sub-folders of the selected start folder.
Have it look only for MP4 files and remove the filename and comment metadata.

I tried your MODIFY batch button and chose mp4, and subfolders and selected remove "file comment" (could not pick filename field as well so I was going to run it twice)
I used a sample of 40 folders inside my test folder on an ssd drive and after about 7 minutes it completed the process but none of the comments were removed.
I tried it again with Title field and got the same results.

If I selected the individual folder I could edit or clear the fields but I could do that from windows in file properties - details and apply. I was hoping to go through my collection  of several thousand mp4 files without having to edit each one separately.

Maybe I'm doing something wrong.

Hello
It seems to be a (big) bug
i'll fix it quickly, thank you for your report!
Jean