Many video file extensions not registered by VLC and unable to register them manually

Question

tl;dr A recent installation of VLC VideoLAN on freshly installed Windows 11 revealed that many popular video file extensions are not registered with this player (many, many others are). I am unable to register them manually because I can't find them on the list of available extension in Default Apps. What should I do? How to manually register some file extension with some (default) applications in this case?

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The problem with video file types

I have a problem in freshly installed Windows 11 that certain well-known apps (VLC, IrfanView) does not register all of their file extensions correctly. I don't know why.

For example, I have just installed VLC and it registered many extension that it supports, but not .mp4:

When I try to fix this by going to Tools → Preferences → Operating System Integration and clicking Setup file associations..., I see a message saying: "To change your default apps, go to Settings → Apps → Default apps". So this is pretty much a vicious circle.

I have tried to manually bind .mp4 extension with VLC program, but to my extreme surprise I cannot find it in my system:

The same goes for virtually every video file extension that I use daily (namely: .avi, .wmv, .mkv). A lot of "weird" extensions are registered, but not these ones:

Some more observations

The file's icons all the time seems to be the one from Windows Media Player:

It remains unchanged from the very installation of Windows 11 even though WMP was removed few days ago.

When file is stored in OneDrive then double-click behaviour is as follows:

• When clicked for the first time -- downloading the file to local disk
• When clicked for the second and following times -- an icon / file status changes from Keep on this device to Always keep on this device and back; no program is ever launched

When file is stored in non-OneDrive location then double click depends on when the file execution attempt was made. When in Total Commander, following error message is shown:

When file is double-clicked in Windows Explorer then Pick application dialog is displayed:

Unfortunately, in Windows 11 the Always use this app... checkbox is no longer available in above mentioned window and picking application process must be repeated with every file execution.

The same problem with image file types

I recall that I had an exactly the same problem with IrfanView registering all of its image extensions, but not the popular ones: .bm, .jpg, .png and .gif. I also couldn't list them on the list in Default Apps.

But, after a day or two, some magic has happened and these extensions started to appear on the list. And I could register them with IrfanView manually. This time I wasn't so lucky and nothing has changed for past 2-3 days.

The question

This is a quite long post that narrows down to a simple question:

What to do in this case?

Is there any way in Microsoft 11 to add a file extension registration, if that extension doesn't appear in Default Apps window? Is there any system-wide way or must I use some third party software?

Answer 1

In my case neither of answers already provided here did not work¹. So I decided to post a third option.

Inspired by some article, I used the wonderful SetUserFTA utility. Its author managed to reverse-engineer Microsoft hash algorithm needed for setting file extensions binding. Thus this program will not only register selected file extension with the application of your choice, but it will also generate required hash, preventing Windows from resetting this binding.

For registering .avi, .mp4, .mpg and .mkv video file extensions with VLC run these commands one-by-one:

SetUserFTA .avi VLC.avi.Document
SetUserFTA .mkv VLC.mkv.Document
SetUserFTA .mpg VLC.mpg.Document
SetUserFTA .mp4 VLC.mp4.Document

For registering .gif, .jpg, and .png image file extensions with IrfanView run these commands one-by-one:

SetUserFTA .gif, IrfanView.GIF
SetUserFTA .jpe, IrfanView.JPG
SetUserFTA .jpeg, IrfanView.JPG
SetUserFTA .jpg, IrfanView.JPG
SetUserFTA .png, IrfanView.PNG

You must run this from either cmd, PowerShell or Windows Terminal (new toy in Windows 11).

For other file types and applications I advice you to run SetUserFTA.exe get once and carefully check, if you don’t have some other bindings incorrect or messed up.

¹ _{The w32sh's answer didn't because I already had Microsoft Photos, Grove Music and Films & TV applications uninstalled so resetting them brought no results. The DrMoishe Pippik's answer did not work, because I had no Change button in Properties and no Always use this app to open... checkbox (well... I had, but only after a certain of time and I still don't know what magic had happened that made this working after a while...).}

Answer 2

(From Can't Associate JPG/PNG Files via Default Apps in Windows 11)

IrfanView setup is known to cause this issue.

Launch PowerShell and run these commands one by one:

Get-AppxPackage Microsoft.Windows.Photos | Reset-AppxPackage
Get-AppxPackage Microsoft.ZuneVideo | Reset-AppxPackage
Get-AppxPackage Microsoft.ZuneAudio | Reset-AppxPackage

Answer 3

In Windows 10 (and hopefully, this works in 11), to add an app to the Open with> list,

• Right-click on a file with that extension (e.g., MP4).
• Select "Open with>*, then Choose another app.
• Click on More apps (you may need to scroll down to see that choice).
• Set Always use this app to open .MP4 files.
• Click on Choose another app on this PC (again, scroll down if needed).
• Browse the file system to pick your preferred application (VLC).

You can also use a third-party tool, such as Nirsoft's free FileTypeMan, to edit the file associations.

See also *Set or Change File Associations & Extensions in Windows 11/108 from the Windows Club.

Admittedly, these are s l o w procedures to add many default file type handlers; some batch procedures might no longer work due to security changes.