I haven’t done this yet, but I wanted to take notes for when I do this. Follow this guide to set custom file extensions in Windows 10.
1. Setup computer the way you want
dism /online /export-defaultappassociations:"C:\Temp\IE-DefaultBrowser.xml"
NOTE: DO NOT delete lines from this.
# This didn’t work, what DID work was:
Dism /Online /get-DefaultAppAssociations >C:\TEMP\DefaultApps.txt
# Then just rename to XML.
- On new computer:
Dism.exe /online /import-defaultappassociations:c:\temp\CustomFileAssoc.xml
# Your file will be copied in \Windows\System32 with the following name OEMDefaultAssociations.xml
- Or through GPO:
Configure the following policy Set a default associations configuration file located in Computer\Policies\Administrative Templates\Windows Components\File Explorer.
If this group policy is enabled and the client machine is domain-joined, the file will be processed, and default associations will be applied at logon time.
To control only some extensions, see the reference.