How to Fix “No Video with Supported Format and MIME Type Found” in Firefox

When encountering the “No video with supported format and MIME type found” error in Firefox, users typically see a blank video player or error message when trying to stream videos. This happens because the browser can’t find a compatible video format or MIME type. The error is often due to missing or outdated video codecs, like MP4, WebM, or Ogg.

The most common cause is missing media components on certain Windows versions, like Windows N or KN editions, which don’t include media features by default. Other triggers include corrupted browser cache, conflicting browser extensions, or an outdated version of Firefox.

Some websites may also use outdated technologies, like Flash, which complicates video playback in Firefox.

Now that you know the causes, let’s discuss the solutions to solve this error.

1. Install Adobe Flash Player

Installing Adobe Flash Player in Firefox can help when websites still use Flash for videos. Some sites haven’t switched to HTML5 yet. Adding Flash allows your browser to handle these older formats and removes the “No video with supported format and MIME type found” error.

1. Download Adobe Flash Player from the official website, selecting the correct web engine option for Windows 10/8.
   
2. After downloading the executable, install it with administrator privileges and restart your computer. Try accessing the video again.

2. Clear Cache and Cookies

This issue occurs when outdated or corrupt cache files stop the browser from loading new video data. Clearing cookies and cache removes these files, allowing Firefox to update site data and address playback errors like “No video with supported format and MIME type found.”

1. Open Firefox and click the Menu icon at the top right.
2. Select Options from the menu.
3. Go to Privacy and Security in the left pane.
4. Click Clear History and choose Everything for the time range.
   
5. Select Clear data, ensure all options are checked, and press Clear now if prompted.
6. Restart your computer and try accessing the problematic website again.

3. Install Media Feature Pack (for Windows N/KN)

If you’re using Windows N or KN edition, install the Media Feature Pack. These versions lack the media features needed for video formats like MP4 or WebM, causing the “No video with supported format and MIME type found” error in Firefox. Installing the pack adds the necessary codecs for video playback.

Navigate to Microsoft’s official website to install the Media Feature Pack for N and KN versions of Windows 10 and download the executables to an accessible location. Install them and restart. Then follow Solution 1 and install Flash. Restart again and try accessing the website to see if the error persists.

4. Reinstall Firefox

Outdated or damaged Firefox files can stop videos from playing. Reinstalling the browser removes problems blocking video formats or MIME types. This gives you a fresh setup with the latest updates, helping the browser handle media content correctly.

1. Press Windows + R, type “appwiz.cpl” in the dialog box, and press Enter.
2. In the application manager, find “Mozilla Firefox,” right-click it, and select Uninstall.

3. Uninstall all Mozilla products and restart your computer. Visit the Mozilla Download site to download the latest version. After installing, try accessing the video again to see if the error is resolved.

5. Use Another Browser

If the problem persists, try using another browser like Chrome. Chrome supports many video formats and codecs, avoiding the issues Firefox might have. This switch offers easy video playback without extra fixes.

Navigate to the Chrome download website and download the installer. Install Chrome, then try accessing the video again to see if the issue persists.