How to Transfer a Windows Activation Key to a New Computer

1. Uninstall Windows from your old computer by restarting your computer and pressing the 'F8' key while Windows is starting, in order to enter Safe mode. Click 'Start' and 'Control Panel', and then select 'Add or Remove Programs' in Windows XP or 'Uninstall a program' in later versions. Double-click your version of Windows from the list of installed programs and confirm 'Uninstall'.
2. Install Windows on your new computer by inserting the original disc in the CD/DVD drive and following the onscreen instructions. When prompted for an activation key, enter the key from the original CD or DVD box. Windows will attempt to register online and will show the error message ''The product key you typed is already in use.'
3. Click 'Start' and 'Run'. Type 'cmd' in the 'Open' box and click 'OK'. Type 'slui 4' (without the quotation marks) and hit 'Enter'. The Windows Activation screen will open.
4. Click on the drop-down box, select your nearest location from those listed and click 'Next'. Call the listed toll-free or toll number. In some locations you can send an SMS text message. Use your phone to enter the installation ID code shown on the screen.
5. Type the confirmation ID you get from the phone system in the onscreen boxes and click 'Next'. Click 'Finish' to complete the activation. Restart your computer if prompted.