The Edit option pops up in Windows after right-clicking a file type in Windows Explorer. Windows associated one software program that can be used to edit that file type. For image files it is usually Microsoft Paint while text documents are usually opened in Notepad. Those applications are set in the Windows Registry where they can be changed so that Edit will open a different application.
It is actually pretty easy to change the default edit application in Windows to another one providing you got the location in the Registry to do so. Now, to change the default Edit application open the Windows Registry by pressing [Windows R], typing [regedit] and hitting [enter]. Locate the following Registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\SystemFileAssociations
In there you find all the different file types and they association. The order is filetype > shell > edit > command. Not every filetype has that chain but the most common ones do. To edit the default text editor in Windows you need to locate the text subkey and follow the path mentioned above until you reach the command key. There should be only one Default entry in there:
%SystemRoot%\system32\NOTEPAD.EXE %1
To change the program that opens when clicking on the Edit option in the right-click menu simply change the path so that it leads to the application that you want to use, for example
"c:\program files\notepad++\notepad++.exe" "%1"
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The above works but isn’t it easier to just use right-click [Open With ...], navigate to desired program and tick [Always use this program]?
Alec: You sometimes have a default application and a handful of other applications that you use to open a certain file type. Say, you open images in your image viewer usually but sometimes want to use a different application to view them.
how do I edit to tick “notify followup via email” if forgotten in initial post?
You cannot. All you can do is leave a second comment and check the box there.
What sucks is that there used to be a dialog for this. Sure, I could do it in the registry, but why did microsoft feel the need to dumb down and remove functionality when they built their newest OS?