I then changed name in MC and "update tags from library". The title in explorer indeed changed
Did the change in that direction work for an MP4 file?
I just tested and MC wrote the change to a sidecar file, even though I have the "update tags when file info changes" flag ticked, but also have the "Store tags is external sidecar files if the file type does not support tagging" option set to Video. When I set the "Store tags is external sidecar files if the file type does not support tagging" option set to nothing the "Update tags from library" failed.
I'm pretty sure I read somewhere that MC won't update MP4 video file tags. Which I thought was strange at the time.
Tagging in different file formats is all about mapping of fields. Here is a
nice reference. Note that in iTunes MP4 files, the Title field is called . . . Šnam, which I believe is short for Copyright Name.
Anyway Daveg, if what you want to do is remove the contents of the Title field displayed in Windows Explorer, simply do that in Windows Explorer.
1. Select one or more files in Windows Explorer.
2. Right click the files and select properties.
3. Select the Details tab.
4. Click the "Remove Properties and Personal Information" link at the bottom of the dialogue.
5. Click the "Remove the following properties from this file:" button
6. Tick the "Title" field.
7. Click OK to save the changes, and OK again to exit the Properties dialogue.
Done.