Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I work alot with billing and files the bank etc. send me files that have date extensions or some counter as an extension:

eg file1.20110315 or file2.123

So the extension changes every time I receive another file.

Is it possible to associate all file types that end in numbers or if not any unknown file types with notepad(++)?


share|improve this question

migrated from Mar 15 '11 at 16:34

This question came from our site for professional and enthusiast programmers.

What OS are you using? – David Oneill Mar 15 '11 at 18:02

You can edit the openas command of the Unknown type, i.e.


Alternatively, you can add a new command if you want to keep the Open As command.

If you want to make Open with Notepad++ the default, edit the default value of the HKEY_CLASSES_ROOT\Unknown\shell subkey.

share|improve this answer
Yup, this is the correct method to register unknown filetypes. The HKCR\* key is for all files. For the record, I too would not recommend setting a text-editor as the default open command for all or unknown files. Instead, set a hex-editor as the default open command, and add a separate “notepad” command for the text-editor. – Synetech Mar 15 '11 at 19:07
To get this working I changed HKEY_CLASSES_ROOT\Unknown\shell\openas\command\(Default) to "C:\Program Files (x86)\Notepad++\notepad++.exe" %1 . I also had to rename HKEY_CLASSES_ROOT\Unknown\shell\openas\command\DelegateExecute to HKEY_CLASSES_ROOT\Unknown\shell\openas\command\DelegateExecuteBackup – rob Dec 18 '12 at 15:46

You can assign the file type "*" in the registry with Notepad++. But I won't reccomend this, since all files, even binary ones, dll's and so on will be associated then.

share|improve this answer
this is not what have been asked. – Luixv Mar 15 '11 at 16:08
But it is a relevant answer, and a possible solution. – CajunLuke Mar 15 '11 at 16:42

The article Add "Open with Notepad" to the Context Menu for All Files describes how to do something similar to what you want, and could easily be changed for use notepad++.

I'm not aware of a way to do it for all numeric extensions.

share|improve this answer

You must log in to answer this question.