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Verifying a Microsoft licence: how to spot fakes

Verifying that a Microsoft licence is genuine mostly comes down to recognising fake offers before you buy. Here we show the typical signs of counterfeits and dubious offers, and which test is ultimately the only truly reliable one.

At a glance

How do you spot a counterfeit Microsoft licence? We show the typical signs of fake offers and how to reliably verify a licence is genuine.

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Typical signs of fake offers

  • Unrealistic price. A price far below the usual market level is the clearest warning sign of a problematic offer.
  • Wrong key format. A genuine Microsoft key has 25 characters in five groups of five. Other formats are suspicious.
  • No invoice, no support. Anyone who fails to provide a VAT invoice on request and cannot be reached is not offering a genuine business relationship.
  • Pressure and urgency. Countdown timers, only a few left, buy now. Reputable providers don't need such tactics.

The only definitive authenticity test

Microsoft does not operate any public database in which you could check a licence key in advance. Checking the format helps rule out obvious nonsense, but proves nothing.

The only definitive test is activation. If Microsoft's servers accept the key and report the software as activated and genuine, the licence is valid. That is precisely why reputable providers offer an activation guarantee: they take on the risk should activation fail.

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Verify for yourself

You can verify the seller yourself, in two minutes

Who stands behind a shop is publicly verifiable: a reputable dealer has a real company with a registry entry and a valid VAT number, both of which can be inspected. The origin of an individual key cannot be proven from the outside, but it can be verified whether a tangible company stands behind the shop. With us, you can even do it live, right here.

Company
Kewee OÜ
Tallinn, Estonia
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17352418
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In the Estonian commercial register

Frequently asked questions

How do I check whether a Microsoft licence is genuine?

Only to a limited extent in advance, for example via the key format. The definitive test is activation against Microsoft's server. If the server accepts the key, the licence is valid.

Can I have a key checked before purchase?

Microsoft does not provide a public verification database. More reliable than a pre-purchase test is to buy from a provider with an activation guarantee who takes on the risk.

What if it turns out that the licence is not genuine?

With a reputable provider, the activation guarantee applies: free replacement or money back. With a disreputable provider, the money is usually lost, which is why the choice of provider matters before the purchase.

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About Keywi24

Keywi24 is a Swiss online shop for verified pre-owned Microsoft and antivirus software licences. The team has in-depth market knowledge from over five years of experience. Our goal is not to become the largest licence shop, but the most trusted.

That’s why we don’t invest in marketing hype, but in 90 days of real technical support after every purchase. Legal basis: CJEU ruling C-128/11 (03.07.2012) and Art. 12 para. 2 URG.

Mon–Fri 08:00–18:00 CET+41 800 20 00 07 (free)Live chat response usually <5 min90-day money-back guarantee