Associate a File Without an Extension to an Application

Here’s something I never knew was possible.  After all these years of using Windows I always thought it was impossible to associate a  file without an extension to an application.  Why would I want to do this?  Simple.  Sometimes applications do not add a file extension to files.  This seems to be the case when working with files from different operating systems.   In my case, I need to inspect some app settings that my phone app is writing and it does not add .xml to the end of the file.  The app I use to retrieve these settings prompts for the app I want to open it with AND I have to choose each time.  This adds extra steps to my workflow and I almost always open files without extensions with Notepad++.  Here’s a simple way of making all files without an extension open in Notepad++ when trying to open them:

  1. First add Notepad++ to your Path variable.
    1. Advanced System Settings>Environment>System variables>Path>Edit
    2. In the Variable value section, add ;C:\Program Files (x86)\Notepad++
    3. Note that this is for a 64-bit Windows.  If you are using 32-bit the Path would be ;C:\Program Files\Notepad++
    4. Be sure that you add the semicolon before you add the path to Notepad++
  2. Reboot
  3. create a .reg file and put the following in:
  4.  Then save the .reg file and merge it


Now, when you double-click files without an extension they will be opened with Notepad++ !

If you prefer Sublime Text or Notepad you can change the last line in the reg key.  I totally took the lazy way and added it to my Path since I couldn’t figure out how to escape the double quotes for the command. (And by “couldn’t figure out” I mean “didn’t spend more than 60 seconds”.)  If you figure out how, leave a comment below.  Oh and by the way, this isn’t totally hacky – Microsoft has a KB on it.

Here’s the .reg key for regular ol notepad (*yawn*)


3 thoughts on “Associate a File Without an Extension to an Application

      1. Hi Thank you. Sorry, what I mean is, what is the name of .reg file and where to merge it? I can understand the first 4 steps. Just unaware about the 5th step.

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