I see many websites that sell very cheap windows 10 product keys

Hi Sura,

• There's no telling if Microsoft acknowledges these websites, but it's likely.
• Most of the time, these sellers provide volume license keys, or keys that are used by organizations, which are usually stolen. The "volume" in volume license keys means that it can be used and activated with a volume, or a mass, of computers. They are not meant to be used in a personal setting.
• These sites are no way affiliated with Microsoft, they are not authorized resellers.
• Refer to the second question.
• It doesn't seem that Microsoft is approving of what they are doing. It may work for some people, but for some others, they find that their license might deactivate out of nowhere and be deemed as non-genuine.

I'd recommend that you purchase from a known authorized reseller, or through the Microsoft Store directly, if you want to guarantee to get mileage out of your Windows license, because it's not worth going through the trouble of having your license deemed illegitimate later on.

Hope this helps.

These sites generally sell volume license keys. And more than often they fail or Windows is not able to activate them or they fail later on when number of license keys exceed in Microsoft servers than what was permitted.

You should buy the keys only reputed sellers where you get good support / replacement guarantee.

The reviews which are written there generally cooked up. Don't fall for them.

The are likely reselling MSDN keys.

About MSDN or TechNet Product Keys

They are genuine Microsoft product keys, they are actually retail licenses, but it is intended for a particular product channel either the Microsoft Software Developer Network (MSDN) or TechNet for IT Professionals who pay a subscription fee. The main purpose is for evaluation purposes. The great thing about them, unlike trial Microsoft software, MSDN or TechNet keys don't expire. Because the agreement under which the subscription is provided is a single license, none of the software should be distributed outside of it. Even though its $50,000 worth of licenses, it is for one person only to use and no one else. Unfortunately, regardless of the licensing terms, persons still abuse the program, either giveaway product keys or resell it on auction sites. Microsoft licenses it in good faith that customers won't do so, but I guess human nature wins out.

In your case, what probably happened is, you bought an MSDN licensed key, which carries up to 10 activations unlike full packaged retail licenses which only carry 1 activation. The person who sold it to you probably sold it to 10 other persons. Somewhere along the way, one of those persons might have installed it on a second system, activated it, because it went past 10 activation threshold, Microsoft detected it that it was being abused and blocked the key from further use.

Hi mEverBlack,

Sorry that I didn't tell you more information.

What I also found is that the sellers just sell product keys to the buyers. The product keys can use in the new computers and new windows. The sellers also claim that the keys are retail version (Full Package Product). And they also get many good reviews from buyers. I see some of the buyers reviewed that they got the message when typing "slmgr /xpr" in CMD, "The machine is permantly activated". I will attach the link for you to see. 

https://shopee.co.th/Windows-10-Pro-Home-Retail-(ย้ายเครื่องได้-แท้100-)-i.33325706.929177354

In this Thai website, the seller is selling windows 10 product key retail version only at 140 baht, which costs around $4.49. In the reviews of the buyers, they love it! 

The keys give Digital License actvation method and the message "The machine is permanently activated"

I don't know how the sellers can sell Windows 10 Professional Product Key at this cheap price? 

Has Microsoft been violated?

Sura,

I assume they're talking about digital entitlements. Simply put, a license can be unique to your computer given it retains its original motherboard, and you won't have to ever enter a product key when you reinstall Windows.

This can happen on whatever route you go, those sellers, or through Microsoft directly. As long as your license is valid, you can reinstall Windows without a product key, which is convenient.