Clean Install of Windows 7 from a Windows 7 Upgrade disk?

I recently tried to upgrade a PC to Windows 8, however, due to problems with crackling on the sound output I decided to return to Windows 7 (and yes, I did install the motherboard and soundcard drivers).


My copy of Windows 7 is an upgrade edition, meaning I have to do a clean install on the Windows 8 drive to return to Windows 7 as Windows 8 is recognised by the Windows 7 installation disk as a newer version of Windows.   I thus need to delete the partition on which Windows 8 was installed to achieve this.

I was therefore faced with the situation of installing my upgrade edition of Windows 7 on a completely blank hard drive.   It installed, however, on reaching the product key entry screen it rejected my product key (i.e. where you enter xxxxx-xxxxx-xxxxx-xxxxx-xxxxx).   Note I am NOT talking about Windows online activation and, yes, I did enter the product key correctly.


In order to persuade Windows 7 to install, I thus seem to need to do one of two things:


1) Install an older version of Windows first (I happen to have an old XP installation disk); or


2) Buy a clean install product key.


I have, however, read about double install.   Does this mean if I install Windows 7 on itself (i.e. upgrade from Windows 7 to Windows 7), it will recognise my product key?


Many thanks in advance,




Question Info

Last updated December 19, 2019 Views 14,485 Applies to:

You can always skip entering the product key and complete the installation.

Reinstalling with a Windows 7 Upgrade DVD:

If you initially bought a Windows 7 Upgrade, upgraded your computer and decided later you want to reinstall Windows 7 you might be wondering what you need to do if you want to reinstall Windows 7 without installing your old version of Windows 7 first.

Microsoft made some changes to how validation works, part of this is to reduce casual copying and piracy. Previous versions of Windows such as Windows XP Upgrade simply requested that you insert a qualifying disc during the installation. Now anybody could simply borrow a disc, whether it was Windows 98,  ME or 2000 which there are no shortage of, to use as a qualifying product. Of course, this is in the best interest of Microsoft’s financial bottom line at your expense. This inconvenience can be minimized with a smart little trick when using the Upgrade DVD. First lets look at what happens when we do a clean install with the upgrade DVD:

This is the message you will receive when you attempt to enter a product key for a Upgrade version of Windows 7. The simple workaround is to skip entering your product key for the time being and click Next. Complete task such as setting up your account name, password, time zone etcetera.

Once you arrive at the Windows 7 desktop, click Start, right click Computer then click Properties.

Scroll down to Windows Activation, then click the link that says xx days to activate. Activate Windows now

Enter your product key, then click Next

Click Show me other ways to activate

Click Use the automated phone system

Click Next again

Select your country

Call the number displayed on your screen to get a confirmation ID. Please hold on to speak with a live person, skip using the automated system. Explain your situation with the agent and they will provide you with a confirmation ID to enter into the blank fields. Click Next and Windows 7 should be activated. A minute or two longer than using the internet, but faster than doing two installations.

Windows Insider MVP
MVP-Windows and Devices for IT

8 people were helped by this reply


Did this solve your problem?

Sorry this didn't help.

Great! Thanks for marking this as the answer.

How satisfied are you with this reply?

Thanks for your feedback, it helps us improve the site.

How satisfied are you with this response?

Thanks for your feedback.