Method 1: Manual
- Right Click on My Computer and Select Properties.
- Wait a second for windows activation details to get populated.
- Click on Change Product key link after your Windows 7 activation details are populated.
- Enter New Product Key and click on next to activate your windows 7
Method 2: Command Prompt
- Click on start and type command (cmd) with run as administrator
- Now type following command
“slmgr.vbs -ipk <insert your new product key here>”
- To activate windows after changing the key, run “slmgr.vbs -ato”