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 How to Clean Install Vista from an Upgrade Disc

If you have an upgrade version of Vista, Microsoft require that you install the old operating system prior to performing the upgrade, which is quite ridiculous when you consider that XP had the ability to clean install from an upgrade disc, however there is a way to clean install Vista from an upgrade disc, and it's fairly straightforward. The only drawback is it takes longer to install this way, but at least it's clean.

Be aware that if you do not own a qualifying operating system to be upgraded to Vista then you are in violation of Microsoft's EULA (End User License Agreement) for the upgrade version if you use this procedure.

Step 1:

Boot from the Vista upgrade DVD and click Install Now:

 

    
Step 2:

When the installer prompts for a product key, uncheck the option to Automatically activate Windows when I'm online and do not enter a product key, leave the field empty:

   
Step 3:

Click Next. Vista will ask you if you want to enter your product key. Click No:
Step 4:

Choose the edition of Vista that you've purchased and install Vista:

    
Step 5:

Once Vista is installed, boot it up and log on. Insert the upgrade DVD into the drive and run the installation once more from within Vista.
    
Step 6:

When Vista asks for your product key again, give it the product key for your upgrade. Choose the edition you have purchased then select either Upgrade or Custom (Advanced) and let Vista install again.

Vista will proceed to upgrade the Vista you installed first. Once the installation is complete you can activate Vista when you're ready.