[Fix] Can’t associate .mp4 files with iTunes

When you right-click on a .mp4 file, click Properties, and click the Change button, iTunes may not be listed in the Open With dialog. It may not be listed in the Open With submenu as well.

When you click “Look for more apps on this PC” in the Open With dialog, you wonder where the iTunes executable is. Since iTunes is a Store app, you may be unable to locate it quickly. It won’t be found in “C:\Program Files” or “C:\Program Files (x86)”.

The result is the same if you open Default Apps to associate .mp4 files with iTunes.

Resolution

To add iTunes to the Open With dialog for .mp4 files and associate .mp4 with iTunes, follow the steps below:

Please run the following command from a Command Prompt window:

reg add "HKCU\Software\Classes\.mp4\OpenWithProgids" /v AppXgw8jsesna2s0kjf6w9gv1d36xjhv8qme /t REG_NONE /f

iTunes should now be listed in the Open With menu and the Open With dialog.

To associate .mp4 with iTunes, right-click on a .mp4 file, click Properties, and click Change.

Select iTunes from the list and set it as the default.

That’s it.