Fix NS_E_ASX_INVALIDVERSION (0XC00D106A) in WMP

Quick answer

Convert the .asx file to .wpl or update Windows Media Player to the latest version—that's the whole trick.

Why this happens

You've got an old .asx playlist that was created for Windows Media Player 9 or earlier. The file header contains a version number (like 3.0) that modern WMP versions (12 on Windows 10/11) don't fully trust. Instead of playing the playlist, WMP throws NS_E_ASX_INVALIDVERSION (0XC00D106A). It's not a corrupted file—it's a compatibility gap. I see this all the time with legacy media servers that still serve .asx playlists from the early 2000s. The playlist itself is probably fine; the version tag is just stale.

Fix steps

Try the latest WMP—On Windows 10/11, ensure you have the latest Media Feature Pack or WMP update. Go to Settings > Update & Security > Windows Update, check for updates, and install any pending. Restart your PC. This rarely fixes it, but it takes 30 seconds.
Convert the .asx to .wpl—Open the .asx file in Notepad. You'll see something like:
```
<ASX version="3.0">
```
Change that to version="3.0" is fine, actually—the problem is WMP expects a newer schema. The quickest fix: copy the playlist content into a new file with .wpl extension. Or use a free tool like Format Factory to convert. But honestly, manual conversion is easy:
Rename the file to .txt, edit the header to <?wpl version="1.0"?>, and adjust the entries to WPL format. That's tedious for large lists.
Use VLC instead—If you just want to play the content, VLC handles old ASX files without complaint. Install VLC (free), open the .asx, and it plays. Not the fix for WMP but gets you listening.

Alternative fixes

If conversion sounds like a chore, check the file itself. Sometimes the .asx has a version attribute that's off. Open in Notepad, look at the first line. If it says <ASX version="1.0"> or similar, bump it to 3.0. Save, try again. That works for some cases.

Another thing—don't bother reinstalling WMP. That rarely helps because the player isn't broken; the file is ancient. I've seen people waste an hour on that.

Prevention

Always generate playlists in current formats. If you're maintaining a media server, export playlists as .wpl or .m3u8 instead of .asx. And if you're downloading old playlists from the web, expect this error. Keep VLC installed as a fallback—it's the Swiss Army knife for format issues.

Pro tip: If you're stuck with many .asx files, write a quick PowerShell script to batch-convert them to .wpl. It's a 10-minute job and saves you forever.