I'd been hassled by a subset of Microsoft MVPs for providing this guide however its a corner stone of the Windows Reinstallation Guide and one of the main reasons I designate this guide as "unofficial".
I have therefore compiled together complete information including download links to Windows Vista and Windows 7 Reinstallation media. This includes the OEM system locked preinstallation activation mechanism found in the Dell Windows Vista Reinstallation DVDs and Dell Windows 7 Reinstallation DVDs. These are now incorporated into the Windows Reinstallation Guide. For full instructions including the download links see:
Windows 7 Player 1: YouTube
Windows 7 Player 2: WordPress
Windows Vista Player 1: YouTube
Windows Vista Player 2: WordPress
how come the products keys do not work…I installed windows 8.1Pro and can not activate it why?
What .iso did you use? Is your license OEM or retail? What key are you using to activate, a generic key won't activate Windows 8.1 Professional.