Windows 7 advanced users have must noticed this that they can change the product key of their copy using command prompt. There is an easy method to do so. This is an alternating way for what we do using System Properties.
How To : Change Windows 7 Product Key Using Command Prompt
If you are good in command line then you must try this. The method is as follows:
1. Open administrative Command Prompt.
3. Now type the following command and hit Enter:
slmgr.vbs -ipk YOUR PRODUCT KEY
4. If the above entered key is new, type the following command and hit Enter key:
slmgr.vbs -ato YOUR PRODUCT KEY