Windows 10: Apps not being set as default opener for some certain file types

My Windows 10 Pro OS build no. is 17134.345. When I go to Settings>Apps>Default Apps>Choose default apps by file type, I want to set Notepad++ for opening .asm files. I select .asm, select Notepad++. But still Notepad++ is not set as the default app for opening .asm files. What to do to solve the severe problem?

NOTE: Developer Options are enabled in my PC.

:)

 

app default setting by file type

Hi Richard,

We understand that you're having issues with the default file app association on your computer. To assist you with your concern, you may refer to the steps below on how to change the default setting of your application:

• In Search Windows textbox, search for choose a default app for each type of file and set .PDF and any other file extensions to point to your choice for default
  programs. Do not use Adobe Reader to set the association.
• Navigate to %systemroot%\system32 and locate the OEMDefaultAssociations.xml file. Make a backup of it just in case.
• Open the OEMDefaultAssociations.xml file and keep it open using
  Notepad.exe.
  
• Open PowerShell or CMD and run it as Administrator.
• Enter the following: Dism /Online /Export-DefaultAppAssociations:C:\AppAssoc.xml
• Open C:\AppAssoc.xml with Notepad.exe
• Copy the entire contents of AppAssoc.xml and replace the entire content of OEMDefaultAssociations.xml.
• Save OEMDefaultAssociations.xml.
• Delete C:\AppAssoc.xml (optional).

After doing the steps, you may now change the default file app association for opening .pdf.

Do update us with the outcome and if you need further assistance.

Regards.

 

Unable to set a default app to open a particular file type on Windows 10.

Hi David,



The above issue might have occurred due to the presence of missing system files and folders on the computer.



Before we assist further, did you try setting the default file type application from system
Settings page?



Follow the steps below to set default program/application to open a particular file from system
Settings page and check if the issue is resolved.

• 
  Press Windows logo key on the keyboard, type
  Default programs and select the top most search result.
  
• 
  Scroll down the page and click on Choose default apps by file type from the window.
  
• 
  Locate the file format, click on the program which is set to open the file type and select the application you want to set from
  Choose an App window.
  
• 
  Close the window and check if you are able to open the file type in the application set as default.
  

Write to us with the status of the default application issues experienced on the PC on the same post for further assistance. Your reply is important for us to ensure we assist you accordingly.



Thank you.

 

setting default app by file type

How do you set the Kindle app to be defaulted to .mobi file type? I don't find the .mobi file type listed as a file type.