If you are installing from a new Win95 disk which is different from the one already installed, then you need to use the product ID of the old one. (Right-click "My Computer" / Properties) the number should be displayed. Write it down and use it. Otherwise double-check the product ID Hope this helps > > Have been having numerous minor problems with Win95 system and > > decided to reinstall the operating system. Everything went well > > until I entered the product ID for my Windows95 CD Rom. > > After pressing "Enter" I get "Invalid ID Number". _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Share information about yourself, create your own public profile at http://profiles.msn.com. PCBUILD's List Owner's: Bob Wright<[log in to unmask]> Drew Dunn<[log in to unmask]>