By Ken Marlin, Microsoft Champion and Technical Consultant at Avnet Embedded

What if when you bought a new car and signed the paperwork, there was a clause in the paperwork that gave you permission to drive the older model of the car?

In a sense, you bought the right to use the brand new car but also it included the right to use the older model.  However, the catch was that you had to locate the older model car on your own. That's only one of the many dilemmas involved when it comes to downgrading Microsoft software, but it's probably the one that I get asked about the most.

Of course we are talking about software and not cars, and it's far easier to duplicate software vs. duplicating a car.  But when it comes to downgrading a Microsoft product, there are a number of actions you need to deal with and I hope to shed some light on a few of them to help you grasp the process.

Reasons to Downgrade your Microsoft OS

First, why on earth would you want to drive the older model car? You have access to the shiny brand new car with far more bells and whistles. The answer is you know all your stuff works great with the old car and it's reliable and proven to be rock solid, as well as, you don't have to learn all those new features. For our customers, many of them have their applications certified to work on the older operating systems and for them to update to the new OS involves 12 to 18 months' worth of testing and certifying. They simply want to hang on to the older product as long as they possibly can but they want to run it on a new system.

For this blog, I want to focus in on the top issues that my customers run into when it comes to downgrading Microsoft operating systems.

Let's start with media and keys. For OEM System Builder licensing, if you purchase Windows 7 Professional, the end user has the right to install Windows XP Professional. The issue is the product only includes the media for Windows 7 and the key code on the COA sticker is only for Windows 7. Let's look at the EULA as it states, "Neither the manufacturer or installer, nor Microsoft is obligated to supply earlier versions to you. You must obtain the earlier version separately." So, there it is and that's where Microsoft leaves you.

Important Things to Know about OEM Downgrading

• Microsoft will never provide you the older OEM key code
• Microsoft will never provide you the older OEM media
• OEM licenses are generic and not tied to customers; they're tied to hardware
• OEM media requires OEM keys
• It's okay to obtain an OEM key from an older COA and re-use it on another licensed system
• When you use an older OEM key, it will fail internet activation and force telephone activation
• OEM Windows 7 Pro allows downgrading to OEM XP Pro
• OEM Windows 8 Pro ONLY allows downgrading to Windows 7 Pro—not XP

OEM Windows Server has all the same issues to work through, so if you plan on downgrading from Windows Server 2012 back to 2008 R2, you'll be on the hook for obtaining the older media and keys. The typical response from the customer: “So where on earth do I obtain the older media and keys?!”

Where to get Older OEM Media and Keys

You have a few different options to obtain the older product:

1. You actually may already have an older copy from an older system, so contact your Server Admin and see if he has an extra copy.
2. If your company happens to own Open Volume licenses—you can actually use Open Volume media and an Open Volume key to downgrade as long as it is a license and key that belongs to your company (Open Volume keys are tied to end user companies).  So don't ever make the mistake of using another end user's Open Volume key to perform a downgrade on another customer's servers or systems.
3. Check with me or Avnet's Integration team as we keep a library of older versions handy primarily for our integration customers, but Avnet will always try and help when possible.

Another common response I hear often from customers is: "I called Microsoft and they would not give me a key for the older product. I thought I was supposed to call them, give them my current key and they would give me an older key in return.”  My response: Microsoft will never give you product keys over the phone. You are required to provide your own key and then when you perform telephone activation, Microsoft's automated system will give you an activation code, which people often confuse with a product key. As a Microsoft Champion, I've helped our customers through the downgrading process for years. If you find yourself confused or lost in the Microsoft EULA forest, shoot me an email and I can get you back on track. Sometimes driving that older car and making it last a few years longer is worth it!

Based in Phoenix, Ariz., Ken Marlin is a Microsoft Champion and Technical Consultant at Avnet Embedded. He has over 30 years of Microsoft experience supporting all Microsoft products and programs with specialties in Microsoft OEM System Builder, OEM Embedded and Open Volume programs. He is a regular contributor to http://www.IntelligentSystem.com.

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