Alright, I use a piece of programming software called Blitz3D. All of the codes written in it are exported as .bb files which can be read by the program itself, Notepad or any other text editor. Of course, I want those files to be launched by Blitz3D right as i double-click them. However, as I right-click on one of my codes, choose "Open with", then "Choose default program", I don't see Blitz3D in the list. No problem there, I just click "Browse...", locate the .exe, click on it... But after that Blitz3D is not added to the list of all available programs to open that file with. So, the default program stays Notepad... First of all, I didn't install Blitz3D, I copy-pasted it from my computer class (we were asked to do so in order to work on our projects at home). I've done some research and found out that the problem is within the registry as it doesn't recognize Blitz3D as an installed program, but i wasn't able to find a complete solution. So, any thoughts?