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The hard drive on my pc died and I had to replace it. My pc originally came with Vista and I upgraded to Windows 7. My pc is a Gateway and I can't find the recovery cd anywhere. I have the Windows 7 upgrade installation disc and the product key for both Vista and 7 still but it obviously will not install the full version. What can I do short of having to buy Windows 7 all over again?

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Have you actually tried putting that upgrade disk in? Mine lets me do a full install – Simon Sheehan Feb 10 '12 at 4:07
I haven't yet but as soon as I finish hooking it up tomorrow I will. I just assumed,since it was an upgrade disk, that I couldn't do a full reinstall. – Megan Feb 10 '12 at 4:12
See this question: Where do I download Windows 7 legally from Microsoft – Fambida Feb 10 '12 at 4:13
It's not an "upgrade disk", it's the disk that came with your upgrade license. – David Schwartz Feb 10 '12 at 4:14
You should be able to use the Windows 7 upgrade disc. Have you tried this? If so, where did it fail? – Joel Coehoorn Feb 10 '12 at 4:14

Clean Install Windows 7 With Upgrade Media:

Put simply, the goal here is to clean install Windows 7 on a virgin, unused PC. You can boot and run Setup with the Upgrade media for Windows 7, but when you go to activate, it won't work.

Thanks to Kevin Fisher and a bit of testing, I have a simple workaround that does work.

After performing the clean install, ensure that there are no Windows Updates pending that would require a system reboot. (You'll see an orange shield icon next to Shutdown in the Start Menu if this is the case).

Then, open regedit.exe with Start Menu Search and navigate to:


Change MediaBootInstall from "1" to "0".

Open the Start Menu again and type cmd to display a shortcut to the Command Line utility. Right-click this shortcut and choose "Run as administrator." Handle the UAC prompt.

In the command line window, type: slmgr /rearm

Then tap ENTER, close the command line window and reboot. When Windows 7 reboots, run the Activate Windows utility, type in your product key and activate windows.

A couple of notes here.

Others have reported that simply installing Windows 7 using Upgrade Media and then activating just works. It certainly doesn't hurt to try this, but my guess is that there was a version of Windows on the hard drive that Setup detected, thus making the install and activation work properly.

I have not tested this yet, but I assume if you launch Setup from within your previous version of Windows, choose Custom, reboot, and then wipe out the previous Windows version during Setup, that that will work as well.

And I'm just about positive that the old "install twice" hack from Vista will work too.

Source of Information

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