How to Find a Registration Number
Software companies use registration numbers to help identify customers who have legitimately purchased the software, and restrict access from users who have not paid for the software. Each software developer handles its own registration numbering system, but normally the registration number can be found inside the software program itself. There are also some common places where registration numbers are stored inside the Windows registry.
Run the program and click "Help" from the main toolbar at the top of the screen. Click to select the "About" section to view additional information about the program. The registration number should be listed here.
Search the Windows registry for software entries that contain the registration number. Click the "Start" menu and then select "Run." Type "Regedit" and click "OK" to run the registry editor. Press "Ctrl" and "F" simultaneously on the keyboard to do a search, then type the name of the program. Look through the "Data" section for a long string of letters and numbers. This should be the registration number.
Contact the software company directly. Visit the company's website and look for a "Support" or "Contact" page. Call or email the company and inquire about retrieving a lost registration number for its software.