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Does my Windows upgrade disc require that I have the previous operating system installed?

Question: Leo, I’ve been thinking about reinstalling my operating system but I’m not sure I can with the installation disc that I have. I had Windows Vista and I then upgraded to Windows 7 Home Premium with a disk that states in the upper left corner of the package, “Upgrade designed for Windows Vista”. Does this mean that it will only install if Windows Vista is present? Or will it install Windows 7 Home Premium on a clean hard disk?

I can’t recall ever seeing a disc with an upgrade designed for a specific operating system. That doesn’t mean there isn’t one; it’s just the first time I’ve heard it put that specifically. So, I can’t say exactly what’s required here, but I can absolutely run down the likely and not-so-likely scenarios.

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Previous versions

The worst-case scenario is of course the one you’re probably already worried about.

In this scenario, you would first have to install Vista, and then upgrade Vista to Windows 7. That’s a bunch of work and to be honest, I’m not sure I would do it. It’s certainly not the first thing that I would try.

Most upgrade discs actually don’t require a specific version of Windows. Often, they’ll accept just about any version. And that could very well include the current version.

So I would try using that upgrade disc on your existing system. As part of the installation, I would instruct it to perform a clean install, reformatting the disk if necessary. Just make sure that when you run the installation program you select “full install” and as I said, reformat the hard disk.


I’m not really sure what your goal is here, but if you’re just attempting to fix some problems with the OS, you could also choose to perform what’s called a “repair install” instead which would leave all of your programs and data on the machine.

So, if installing over itself doesn’t work, and you don’t want to take the time to install Vista first, what then? Well, the only practical solution is to go out and purchase a retail copy of Windows 7; or a more pragmatic choice at this point might well be to purchase Windows 8, if you’re going to be spending the money anyway.

Insert DiscAvoiding it in the future

Now, I do have to point out how this all could have been avoided. And if you do end up going that worst-case route of installing Vista and the upgrading to Windows 7, I highly recommend you follow these steps:

  1. Install Windows 7 or 8.
  2. Update that Windows OS so that it’s as current as possible.
  3. Take a backup image of your system using a tool like Macrium Reflect. The free edition will do. This then becomes your new installation media.

If you ever in the future need to start over from scratch, as you’re wanting to do here, the process is very, very simple. You boot from the backup program’s rescue disc, and you restore this image of the newly installed operating system, and you’re done.

It requires thinking ahead a little bit, but as you can see it can really pay off should you ever need it.

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5 comments on “Does my Windows upgrade disc require that I have the previous operating system installed?”

  1. The process is somewhat time consuming but what I do in this situation is (1) backup data, (2) erase hard drive, (3) install Windows 7 using upgrade media but do not enter your product ID or activate, and (4) install Windows 7 using upgrade media again and this time enter product ID and activate. Doing the second install (step 4) is technically an upgrade install even though the original install was not activated.

    This is the same process that Paul Thurrott spells out at the link below.

    I used the “Double Install” method several times without any problems.

  2. At least on older versions of Windows (98 through Vista I have personally tried), the Upgrade Edition will let you do a clean install on a blank hard drive, but will prompt you early in the install to put the installation disc of a qualifying previous Windows version to verify that you do in fact have an older version of Windows to upgrade from, even if it’s not installed at the moment.

  3. Windows has an upgrade disk from Vista to Win 7, I have it and yes you can reinstall windows 7 from the upgrade disk. it works I have done it.

  4. What about that digitalriver .iso? You said that it only works with Windows 7, so it would apply to this article quite well.

  5. I, too, used Paul Thurrott’s article linked above by Douglas Brace both to install Windows 7 with an upgrade disc, originally in a second partition on my Vista laptop and then on an new hard drive when I filled the old one on my XP desktop. So it works whether you have a previous version of Windows on the hard drive or not.


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