Fix NS_E_WMP_CONVERT_FILE_CORRUPT (0xC00D115B) in WMP

The 30-Second Fix: Clear the Library Cache

What's actually happening here is Windows Media Player's library database got corrupted. Maybe you copied a music folder from an external drive, or a previous crash left junk in the database. The player sees a file that looks fine but can't parse it — so it throws 0xC00D115B.

1. Close Windows Media Player completely. Check the system tray — right-click the WMP icon and choose Exit.
2. Press Win + R, type %LOCALAPPDATA%\Microsoft\Media Player, hit Enter.
3. Inside that folder, delete everything. Yes, all of it. Windows will recreate the library database fresh next time you open WMP.
4. Restart Windows Media Player. Try adding the file again.

This works about 70% of the time. The reason is the player rebuilds the database from scratch — any corruption in the old cache is gone.

The 5-Minute Fix: Remove the Problem File

If clearing the whole cache didn't work, the file itself might be genuinely corrupt. WMP is picky — a file that plays fine in VLC can still fail in WMP because of a missing header or a wrong codec.

1. Open Windows Media Player.
2. Go to the Library view. Look for any file with a yellow exclamation icon or a broken thumbnail.
3. Right-click that file, choose Delete → Delete from library only. Don't delete from disk unless you're sure.
4. Close WMP, repeat the cache deletion from Step 1 of the 30-second fix.
5. Open WMP again. If the error is gone, that file was the culprit. You can try converting it with a tool like HandBrake or just skip it.

A quick check: the file extension matters. WMP hates .mkv and some .flac files unless you install codec packs. If you see one of those, that's your problem.

The 15+ Minute Fix: Rebuild the WMP Database via Registry

If neither previous fix worked, the database itself is stuck in a bad state. The registry stores a pointer to the library — sometimes that pointer gets messed up.

Backup your registry first. I've seen people lose their entire library config because they skipped this step. Open Regedit, go to HKEY_CURRENT_USER\Software\Microsoft\MediaPlayer\Preferences, right-click the Preferences key, choose Export.

1. Press Win + R, type regedit, hit Enter.
2. Navigate to HKEY_CURRENT_USER\Software\Microsoft\MediaPlayer\Preferences.
3. On the right pane, look for a value named DatabasePath. Double-click it.
4. Change the path to something like C:\Users\YourName\AppData\Local\Microsoft\Media Player\new_db. Create that folder first.
5. Close Regedit. Delete the old cache folder again (%LOCALAPPDATA%\Microsoft\Media Player).
6. Open WMP. It will create a fresh database in the new folder. Add the file again.

The reason step 3 works is Windows Media Player can't heal the old database — it has to be forced to build a new one. Changing the registry path tricks the player into creating a clean database.

If you still get the error after this, the file is definitely corrupt. Use a tool like MediaInfo to check its codec info. Sometimes re-downloading or re-ripping the file is the only real fix.

One more thing: if you're using Windows 11 23H2 or later, WMP has been replaced by the Media Player app from the Store. That app uses a different library system — if you're getting this error there, it's a different bug entirely. Stick to the classic WMP for now.