I also have problem. ALL topics and ^\d*\s*-*\s* similar strings ware tested, without result.
It never remove simple : 01. C-Block to C-Block for example. I go to Actions quick, then replace with regular extensions, then FILENAME and in lower field ^\d*\s*-\s, or ^\s*[01-19]\d+\s*-\s* and I press OK and still nothing happened. Do I have to do anything extra, to press some other button or?
So a quick update to ALL users. Finally, it works. here is the situation. It does not matter what you write as a string, if you type FILENAME in the first field, IT NEVER WORKS. REMEMBER THAT.
So the magic trick is to use: ^\d+.\s* ,but in the FIELD you put: ARTIST, and on the lower field, you paste: ^\d+.\s* then it changes ONLY the field ARTIST. After that, if all is ok, you have to use the top menu and to choose TAG to FILENAME and all will be good! Thanks to all of you for the support! In return, I will make a video to help other users with this. Cheers!
This is one of the reasons why we always suggest providing screenshots of such Actions.
Sometimes "Two heads are better than one" (or as we call it in German: “Four eyes see more than two”).