Windows Forums member, grr, asked the following question in our suggestion box:
There are 10 or more different types of keys for Microsoft products. example, VLM, KLM, abc, xyz, oem, etc. I have to admit that still till date I’m not having a proper and reasonable understanding of all these different keys. It would be great if a post could be made on the blog explaining the difference for these keys.
In this post, we’ll explain the difference between product keys for Microsoft products.

Microsoft Product Key Types

  • CUS – This custom key requires special actions to activate or install.
  • MAK – This volume license key (MAK) allows multiple activations.
  • RTL – This retail key allows multiple activations.
  • STA – This setup key bypasses activation.
  • VL1 – This is a VA 1.0 key.
  • OEM – This is an Original Equipment Manufacturer key that allows multiple activations.
  • AAA – This retail key is for AA* programs and allows one activation. These keys are issued in batches.
  • AAL – This lab use key is for AA programs and allows multiple activations.
  • AAM – This is a multiple activation key for AA program customers.
  • AV1 – This volume license key (VA 1.0) is for AA programs and allows multiple installations.
  • AV2 – This volume license key (KMS) is for Academic Alliance programs.

*AA = Academic Alliance


Windows 7 Product Keys

There are 4 types of retail consumer keys for Windows 7:
  • Retail key: This key comes with a retail box or download copy of Windows 7, and can be used for a clean install or upgrade.
  • Retail Upgrade key: This key comes with a reduced-price upgrade only version of Windows 7 & can be used for upgrade only.
  • OEM COA Non-SLP key:  This is the regular OEM key without the special BIOS check. This type of key is provided with copies of Windows marked for purchase with a new PC only.
  • OEM SLP key: This key is used for OEM computers that use BIOS-locked activation, used by large PC  manufacturers.
I hope this clears up some questions about the different types of keys available for Microsoft products.
Have a question about Windows? Ask it in our suggestion box and we may answer it like we did with this post.

About Rich

Rich is the owner and creator of Windows Guides; he spends his time breaking things on his PC so he can write how-to guides to fix them.

Free PC tips by email

Search Windows Guides


One thought on “Microsoft Product Keys—OEM, Retail etc. What’s The Difference?”

  1. RSVR85 says:

    I never knew there were so many different key types available. Thanks muchly for the clarification Rich, nice post ;)

Comments are closed.