assign file extension to a certain application

[r0n]

Is there a way to associate an application to a file extension.
For example ".txt" associated with 'Notepad++' (Every time a .txt get's double clicked, it will be opened with 'Notepad++'

I now have a rather long macro that does through the GUI, (right click on file, open "Properties", click button "Change..." , etc...).
I tried to find a more direct way through commandline, but I could not find a way.

Can QM handle this?