# MP4 file Tag editing not working **URL:** https://community.mp3tag.de/t/mp4-file-tag-editing-not-working/71700 **Category:** Support **Created:** [August 5, 2026, 2:00pm UTC](https://community.mp3tag.de/t/mp4-file-tag-editing-not-working/71700 "2026-08-05T14:00:57Z") **Posts on this page:** 1 **Showing post:** 2
### Author: ![ohrenkino](https://community.mp3tag.de/user_avatar/community.mp3tag.de/ohrenkino/32/4843_2.png) [@ohrenkino](https://community.mp3tag.de/u/ohrenkino) #### Post date: [August 5, 2026, 2:08pm UTC](https://community.mp3tag.de/t/mp4-file-tag-editing-not-working/71700/2 "2026-08-05T14:08:06Z")
> [@specops](#): > > The files are in a MP4 format Check if the files are real mp4 files, see e.g. about problems with MP4 files here: > [@Can't change details on Twitter videos](https://community.mp3tag.de/t/cant-change-details-on-twitter-videos/65315): > > 1 Download an .mp4 video from Twitter 2 In Windows Explorer (windows 8.1), right-click on the filename of the file I just downloaded and examine the Properties | Details tag. 3.None of the fields are modifiable. 4 Open that directory in Mp3Tag, select that file, and enter a Comment. 5 It shows in the Comment field in Mp3Tag. 6. Save and close mp3.Tag, 7. Examine the Details in Windows Explorer, the comment isn't there. 8. Open mp3tag, the Comment is still there. In all other instances, t… A check of the file's consistency would also help: > [@How to check files for errors?](https://community.mp3tag.de/t/how-to-check-files-for-errors/44633): > > It’s required and often helps to reduce support cycles to check files for errors before filing a bug report. Symptoms of erroneous files are often missing or wrong bitrate or length audible blips or skips tags seem to be sticky and cannot be removed There are some really good tools to check the files for errors, namely MP3 Diags — identifies many different issues in MP3 files Website: [http://mp3diags.sourceforge.net](http://mp3diags.sourceforge.net) Download: [MP3 Diags - Getting MP3 Diags](http://mp3diags.sourceforge.net/010_getting_the_program.html#binWindows) If the font size in MP3 Diags is … --- _[View the full topic](https://community.mp3tag.de/t/mp4-file-tag-editing-not-working/71700)._