# Unable to read some .mkv files using IDM **URL:** \ **Category:** Support\ **Created:** [December 16, 2021, 2:04pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547 "2021-12-16T14:04:19Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![m3ss1](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/m/dfb087/32.png) [@m3ss1](https://community.mp3tag.de/u/m3ss1)\ **Post date:** [December 16, 2021, 2:04pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/1 "2021-12-16T14:04:19Z")
![Screenshot (82)](https://community.mp3tag.de/uploads/default/original/2X/5/5bee4c0f7f379db5d8dc7ca47c451529ea7f493f.png) mp3tag cannot read Mkv files containing Opus audio, but it can read Mkv files containing AAC-LC format audio. Both files' info is shown in the above image (mp3tag reads the left one but is unable to read the right one). How can I solve this issue? Thank You. ---
**Author:** ![Florian](https://community.mp3tag.de/user_avatar/community.mp3tag.de/florian/32/5759_2.png) [@Florian](https://community.mp3tag.de/u/Florian)\ **Post date:** [December 16, 2021, 3:03pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/2 "2021-12-16T15:03:27Z")
Please try the integrity checking with foobar2000 as outlined here: > [@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 … ---
**Author:** ![m3ss1](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/m/dfb087/32.png) [@m3ss1](https://community.mp3tag.de/u/m3ss1)\ **Post date:** [December 16, 2021, 4:58pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/3 "2021-12-16T16:58:14Z")
Thank you for your reply. foobar2000 integrity check shows: Failed: Corrupted file or unsupported format. When I change the extension from .mkv to .opus or .ogg, the mp3tag does read the file, although metadata like bitrate, length is blank (size is shown). ---
**Author:** ![MotleyG](https://community.mp3tag.de/user_avatar/community.mp3tag.de/motleyg/32/440_2.png) [@MotleyG](https://community.mp3tag.de/u/MotleyG)\ **Post date:** [December 16, 2021, 6:42pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/4 "2021-12-16T18:42:43Z")
You can’t just change the file type by changing the extension. It may allow mp3tag to read some or all of the tags, but it doesn’t fix the issue. I suggest you look for a tool to repair the file itself. Or if you have the original source to rip it again. Something is wrong and the header is corrupt. ---
**Author:** ![m3ss1](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/m/dfb087/32.png) [@m3ss1](https://community.mp3tag.de/u/m3ss1)\ **Post date:** [December 17, 2021, 4:41am UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/5 "2021-12-17T04:41:20Z")
Yes, I passed the file through Mkvtoolnix, and it did convert it to MKV without any error. And now it's being read by mp3tag. The problem is not for one file; it's for all the video files downloaded using IDM, while mp3tag does read the files downloaded using Jdownloader. ---
**Author:** ![Crissov](https://community.mp3tag.de/user_avatar/community.mp3tag.de/crissov/32/6619_2.png) [@Crissov](https://community.mp3tag.de/u/Crissov)\ **Post date:** [December 17, 2021, 11:51am UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/6 "2021-12-17T11:51:00Z")
This sounds like it should be a bug report to IDM. ---
**Author:** ![MotleyG](https://community.mp3tag.de/user_avatar/community.mp3tag.de/motleyg/32/440_2.png) [@MotleyG](https://community.mp3tag.de/u/MotleyG)\ **Post date:** [December 17, 2021, 12:37pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/7 "2021-12-17T12:37:27Z")
These are download managers. I don’t think they would manipulate changes to the actual files. It is much more likely something to do with the source, or original conversion to digital. As always, the first check if mp3tag cannot access something that it should is to check for file integrity. ---
**Author:** ![Crissov](https://community.mp3tag.de/user_avatar/community.mp3tag.de/crissov/32/6619_2.png) [@Crissov](https://community.mp3tag.de/u/Crissov)\ **Post date:** [December 18, 2021, 12:30pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/8 "2021-12-18T12:30:22Z")
Download managers nowadays concatenate fragments of media streams (e.g. HLS, DASH) to reconstruct an actual file. This can go wrong of course. ---
**Author:** ![MotleyG](https://community.mp3tag.de/user_avatar/community.mp3tag.de/motleyg/32/440_2.png) [@MotleyG](https://community.mp3tag.de/u/MotleyG)\ **Post date:** [December 18, 2021, 3:28pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/9 "2021-12-18T15:28:10Z")
Correct. But the end result should still be the same, a file that is complete. If an error occurred during the download and subsequent reconstruction, the download manager should be identifying that. Regardless, once it is confirmed that their is a file integrity issue it must be fixed. Download the file again, or rip from the physical media if available. ---
**Author:** ![system](https://community.mp3tag.de/uploads/default/original/2X/c/ce7035d426cb755a7916793326d23b465222a407.png) [@system](https://community.mp3tag.de/u/system)\ **Post date:** [February 9, 2026, 12:29pm UTC](https://community.mp3tag.de/t/unable-to-read-some-mkv-files-using-idm/55547/10 "2026-02-09T12:29:34Z")