Associate This is a powerful, but easy-to-use, utility that gives you control over your file associations. If you have several programs that can open the same file types, getting the right one to run is a nightmare, unless you use Associate This.
Associate This also allows you to lock a files extension to a particular program, so no other program will hijack that extension. At last, your files will open the way you want them to.
At last, your files will open the way you want them to.