Downloading Problem

I have this problem where when some programs I download instead of installing when I click on it to, the program goes to notepad which makes the program into random symbols and unable to instal or make it work. So is there an option that stops the download from going into the notepad program or do I have to download something? Thanks In Advance

What is that program name?

Find out the program name, and uninstall it, or you may find that you have it set as the default to open stuff with. To change that, right-click on the program and click open as, after that, select a default program like WinRar or whatever.