I know that generally I must rely on Windows prompts to manage the default apps associated to any given file extension or protocol ( https://blogs.windows.com/windows-insider/2015/05/20/announcing-windows-10-insider-preview-build-10122-for-pcs/ ), but I am wondering if there is a file where I can do this manually?
Thanx
The default apps are maintained in the Windows Registry at HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\. It's easy to view and modify the items shown in the Open with > context menu. In the example below, brave.exe and msedge.exe are two choices that are available in that menu.
However, setting a particular app as the user choice is not easily done through the Registry, because the choice is encrypted, as shown below. Microsoft chose to do so to prevent malicious apps from setting themselves as default. Coincidentally, it also made it more difficult for a user to select a non-Microsoft product as default, e.g., replacing Edge as the default browser with Firefox or Brave.
If you want a new application as default, it can be added through the shell menu. For example, to add pestudio as an application that can open any (wild card, *) file when right-clicked, in HKEY_CLASSES_ROOT\*\shell, add the keys and values as shown below, not encrypted.
