Needs a tidy up but you get the idea….
Key Change in WIN7
|Changing the windows product key in windows 7 can be done through the command line;To Start open cmd, by typeing cmd into the start menu search bar, When the cmd icon is shown right click it and select open as administrator.With your administrator cmd prompt open you then type in “slmgr.vbs -ipk ” replacing with the windows key, making sure to include the Dash’s i.e. “4j3h3-3543j-xxxxx-xxxx-xxxxx” and then press enter.
This should then bring up a small box informing you if the key was correct and installed successfully, if the key is incorrect make sure that the key was typed properly and that the cmd prompt is being ran as an administrator.
After successfully installing the key it needs to be activated this can be done by typing slmgr.vbs –ato into the Administrator cmd prompt and pressing enter.
This will then bring up a box informing you if the key activated successfully or not.