Windows 10: Windows 11 default apps unable to find .m4v extension

HelloI am trying to use VLC media player as a default. My problem is as follows:I double click on a m4v video file"How do you want to open this .m4v file" dialogue appearsWhen I choose VLC I've uninstalled windows media player, the file opens in VLCThis happens each time I open a m4vUnder Apps -> Default apps -> Choose defaults by file type there is no m4v!This means that I cannot set any media player as a default for m4vEach time I have to choose how I want to open the fileThis is very annoying and counter-intuitive for me.Please advise.With best regards,SR

:)

 

How to set a default app for extensions?

Hi Tyler,

Which app are you trying to set for .res extension?

Please try to check the app you are trying to set. Is it feasible with .res extension?

I suggest performing the steps below and check if it fixes the problem.

Go to Setting - Apps - Click on Default apps - Click on Choose default apps by file type.

On the left, search for .res extension

Across .res extension, tap on Choose a default

Try browsing for the app.

 

Cant set the default app for extensions

Hi Alex,

Thank you for writing to Microsoft Community Forums.

We'd like to get more information regarding the issue.

1. May I know which app you are trying to set for
   .res extension?
   
2. Could you check the app you are trying to set, if it is feasible with
   .res extension?
   

You may follow the steps mentioned below and check if it helps.

1. Go to Setting >
   Apps.
   
2. Click on Default apps.
   
3. Click on Choose default apps by file type.
   
4. Look for .res extension on the left pane.
   
5. Across .res extension, click on
   Choose a default.
   
6. Try browsing for the app.
   

Hope it helps.

Manjunath H

Microsoft Community - Moderator

 

Unable to change default app by protocol or filetype.

Hi, just considering what is shown in the Open With options, for example:



Here you can see Sumatra is my default reader.





Here you can see Sumatra and Chrome are added to the Open With list, + Edge, a system default.

The choice presented to you for .fdf, .pdfxml, .pdx for example, should depend on whether Bluebeam has correctly registered itself in the appropriate place as capable of handling those extensions.

So, for example, is Bluebeam shown in the Open With list for those extensions?

It is not enough that a program is installed that is potentially capable of handling a file type (e.g. via an Open dialogue) but that it be so registered. That is up to the author to specify.

Application Registration - Windows applications | Microsoft Docs





This opens in Sumatra, my default.

Unfortunately this option in the Control Panel now opens in Settings:



and does not allow you to do what it claims.