Why can’t QuickTime open MP4


QuickTime is a well-known multimedia player developed by Apple that can play a variety of formats including digital video, picture, sound, panorama, and so on. However, consumers are occasionally irritated by the fact that QuickTime Player is unable to open MP4 files, which is the most commonly used video file format.

Many customers are perplexed as to why QuickTime Player is unable to play MP4 files and are unsure how to resolve the issue. If you are having the same problems, please read this article to learn why this error pops up and how to play MP4 on a Mac using QuickTime.

Why QuickTime can’t play MP4

For a variety of reasons, QuickTime Player is unable to play MP4 files. Let’s figure out what’s causing the playback failure in your case before we move on to the remedy.

  1. The video file could be corrupted

MP4 video files can be corrupted as a result of improper file transmission, technical faults, malware attacks, and a variety of other issues. There’s no easy method to tell if your MP4 is corrupted, yet when we try to debug, file corruption is invariably blamed for playback issues. QuickTime has no recovery features, thus if it’s broken, it won’t play MP4.

  1. Old version of QuickTime

If your QuickTime application is unable to open MP4 files, you should first check the version of the application. It’s likely that QuickTime player is unable to read and compress MP4 file data because some new features of video files are incompatible with an older version of multimedia players. However, you should be aware that you need to pay in order to upgrade QuickTime.

  1. MP4 file’s incompatible codec

MP4 includes a variety of video and audio codecs that may be beyond QuickTime’s encoding and decoding capabilities.Although QuickTime supports a wide range of codecs, it is only compatible with MPEG (.mp4, .m4v). As a result, if your QuickTime player won’t play MP4, it’s most likely due to the file being compressed using an incompatible codec.

Other causes for QuickTime’s inability to play MP4 files exist. For example, it could be caused by an incorrect installation of QuickTime or the loss of some crucial parts of QuickTime during download, making QuickTime players difficult to use normally. If your computer or other operating system is infected with malicious software, the MP4 file may be damaged. Here are several appropriate solutions to this problem.

Solutions to fix QuickTime can’t open MP4

  1. Update your QuickTime player

As explained above, the error can be due to the fact that your QuickTime player is outdated. To verify the current version of QuickTime Player, go to the top bar menu QuickTime Player > About QuickTime Player. If you’re using an out-of-date version, you can quickly upgrade it by navigating to your Mac’s App Store and hitting the Updates icon. Then it will display all of the apps that need to be updated; simply click on QuickTime and choose “update.”

  1. Convert MP4 to QuickTime playable format

If you don’t want to try a lot of different things but still can’t get it to work, converting MP4 to a QuickTime-friendly version is always a good option. All you’ll need is a good Mac video format converter. 

Vidmore Video Converter is a top-rated video file converter and transcoder. It is the most comprehensive and powerful multi-format video converter on the market, capable of converting video files to 200+ formats and devices in a matter of seconds without sacrificing quality. 

Using Vidmore Video converter, you can convert MP4 to WAV or other preferred QuickTime Playable format by following the steps below.

Step 1: Open vidmore video converter

Launch Vidmore video converter on your preferred device.

Step 2: Organize your files 

To import the videos you want to convert, click “Add Files” or drag and drop them into the program’s working area. 

Step 3: Select a Format for the Output

Choose a target format for video conversion or a device type by clicking the “Format icon” dropdown arrow. To change the quality, go to “Settings.” You can also convert webm to mp4 files. 

Step 4: Begin the Conversion Process 

To begin converting your video files, click the “Convert all” button. Due to the size of your files, the process may take several minutes.

  1. Restart your PC and QuickTime 

If you’re having trouble with QuickTime not being able to open MP4 files on your Mac, try closing and reopening the program to see if it helps. Alternatively, you could try shutting down and restarting your computer. You won’t need to use any bothersome methods if they help.


I hope this post is useful when your QuickTime fails to open MP4 files. If you have an issue with QuickTime Player not being able to open MP4 files in the future, using a powerful video converter like Vidmore video converter could help resolve the issue once and for all.