In this tutorial, we learn how to open .zip files. First, go to the start menu and search for "regedit.exe", then press enter. After this, a new window will pop up, open the computer icon, then open "current user", "software", "Microsoft", "Windows", then "current version". Now, click on the explorer folder, then the "file exts" folder and ".zip" folder. You should now see three different folders, right click on "user choice", then delete it. Exit this program, and now return to your zip folder. You should now be able to open it without a problem. This should fix your problem for all the files you can't open, so enjoy using this tool!