1. First download Magical Jelly Bean Keyfinder. Its a freeware open source utility that retrieves your Product Key (cd key) used to install Windows from your registry. It allows you to print or save your keys for safekeeping.
2. Run the key finder program. Follow any instructions provided by the software.
3. The numbers and letters displayed by the program represent the Windows Vista product key. The product key should be formatted like xxxxx-xxxxx-xxxxx-xxxxx-xxxxx - five sets of five letters and numbers.
4. Write this key code down exactly as the program displays it to you for use when reinstalling Windows Vista.