I made a stupid mistake and changed the default program that runs .txt files to cmd. Now when I right click .txt files and try and change the default program back to notepad the "Opens With" option is not there anymore. I also tried going into Control panel/Programs/Make a file type always open with a specific program and setting the default program from there. But when I click on it and change it to notepad and click ok nothing happens and cmd is still the default program that opens .txt files. What should I do?