You accidentally open an .mp4 file, picture or a web page with Microsoft Word? After doing that, Microsoft Word will be present in the Windows Explorer Open With menu every time you select .mp4 file types. Every time you open a certain file type (.mp4 .mp3 .html .php .txt .pdf ...) with a particular software, Windows 7 or Windows Vista will automatically add that software inside Open With menu. This can be useful to quickly open a file with another software that is used normally, but it quickly becomes annoying when inadequate software fill up the menu and in this tutorial I will show you how easily you can clean this list and remove those software's that are unnecessary.