How to Choose the Right Volume License Key for Windows

Keys and products (bits for download) for our volume license customers are available on the Volume License Service Center (VLSC) portal. Authorized users of VLSC can use the portal to manage Software Assurance benefits, track licensing information, as well as download products and product keys. Generally speaking, the people with access to VLSC can be from the procurement team or IT management, rather than the implementers responsible for installing and managing the software. This can cause some confusion as the person with access may not always know what type of key to retrieve…and the person asking for the key may not know which key to ask for. This document is aimed at helping all who need to know 1) how Windows Volume License product keys are organized, and 2) how to choose the right one, based on the individual organization’s deployment. Before we go further, it is important to note that not all Volume License customers will have access to all key types; it is very much dependent on the agreement that has been purchased. For more information in that area, review this documentation on the VLSC portal.

With the release of Windows Vista, we introduced two new key types for Volume License customers: 1) Key Management Service (KMS), and 2) Multiple Activation Key (MAK). We will be covering the product keys for all of the Windows editions available to our Volume License customers since the release of Windows Vista (namely Windows 7, Windows Server 2008, and Windows Server 2008 R2). The discussion of volume activation using these keys and methods (implementation, choosing a method, etc.) is out of scope for this document. Check out our TechCenter at https://www.technet.com/volumeactivation for more information on those topics. Lastly, most customers will use both KMS and MAK in their environment, so you will probably need to understand how both keys work and how to choose the correct key(s) from each type.

When choosing a key for Windows, you’ll need to answer two main questions:

  1. What products are being deployed and need to be activated?

  2. Which method are you intending to use: KMS, MAK, or both?

On This Page

Product Keys and Groupings
Key Management Service (KMS)
Multiple Activation Key (MAK)
Conclusion

Product Keys and Groupings

With Windows, the keys are organized in product groupings. There are four product groupings that cover all of the Windows client and Windows Server operating systems. One grouping is for the client editions; the other three cover the server editions. In the figure (below) you can see the four groupings for Windows 7 and Windows Server 2008 R2, and the specific OS editions that fall into each group.

Product Groups

The product groupings for Windows Vista and Windows Server 2008 are very similar.

Product Groups

Read on to discover why these product groupings matter when choosing the right key(s) for your deployment.

Key Management Service (KMS)

Customers will receive a KMS key on VLSC for each product grouping, corresponding to the products that they are entitled to per their Volume License agreement. If a customer is entitled to all Windows operating systems, the VLSC user could see eight Windows KMS keys (four for the current versions and four for the previous release). The following screenshot shows VLSC for an internal Microsoft organization. Note that the key and organizational info has been blocked out to preserve confidential data.

VLSC for an internal Microsoft organization

In this case, this organization has been issued the following KMS keys:

  • Windows Vista – KMS

  • Win 7 – KMS

  • Windows Web/HPC Srv 2008 KMS A

  • Windows Web Srv 2008R2 KMS A

  • Windows Server 2008 Std/Ent KMS B

  • Windows Server 2008R2 Std/Ent KMS B

  • Win Srv 2008 Data Ctr/Itan KMS C

  • Win Srv 2008 R2 Data Ctr/Itan KMS C

Based on that…if KMS is the chosen activation method for the organization, how would the VLSC user know which one to use? First, understand the nature of the keys (e.g. how they behave) and then choose the one for the highest product in the hierarchy being deployed. In this sense the highest in the hierarchy is based on the product groupings (Windows Server 2008 R2 Datacenter is higher than Windows Web Server 2008 R2) and the latest, in terms of release or generation (Windows 7 is bigger than Windows Vista).

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This key type is designed to activate a service, on a designated host system, that can then enable the activation of various editions of Windows installed on individual computers. Therefore, we say that KMS keys are hierarchical in nature.

  • A KMS key is issued to and associated with a particular product grouping

  • Each KMS key enables the activation of the products in a product group, as well as the groups lower in the hierarchy

In addition to understanding the hierarchical nature of the KMS keys, it is also important to know how the different generations of Windows and KMS work together. As I stated above, there are two sets of product groupings, one for the current generation of Windows (Windows 7 and Windows Server 2008 R2) and one for the previous generation (Windows Vista and Windows Server 2008).

  • Each KMS key enables the activation of the products in a product group, as well as the groups lower in the hierarchy

  • In the case of Windows 7/Windows Server 2008 R2 KMS keys, each key will also enable activation of the products in the previous generation (Windows Vista/Windows Server 2008, in this case) using the same hierarchy mentioned in the bullet above.

Examples

Let me run through a couple examples to illustrate this. Then in the next section (Choosing the KMS Key) you will find a simple questionnaire to determine the exact key that you need.

Example 1: Deploying Windows 7 Enterprise and Windows Server 2008 R2 Standard Edition

In this case, Windows Server 2008 R2 Standard edition is the highest product being deployed in the product grouping hierarchy. The associated KMS key for that product is the Windows Server 2008R2 Std/Ent KMS B key. The KMS B key will activate a service that can activate these product groupings:

  • Server Group B for Windows Server 2008 R2, and

  • Server Group A for Windows Server 2008 R2, and

  • Client VL for Windows 7, and

  • Server Group B for Windows Server 2008, and

  • Server Group A for Windows Server 2008, and

  • Client VL for Windows Vista

Example 2: Deploying Windows Vista Enterprise and Windows Web Server 2008

In this case, Windows Web Server 2008 edition is the highest product being deployed in the product grouping hierarchy. The associated KMS key for that product is the Windows Web/HPC Srv 2008 KMS A key. The KMS A key will activate a service that can activate these product groupings:

  • Server Group A for Windows Server 2008, and

  • Client VL for Windows Vista

Example 3: Deploying Windows 7 and Windows Server 2008 Standard

Now, this is the most interesting example. Windows Server 2008 Standard edition is the highest product being deployed in the product grouping hierarchy in terms of edition…but not in terms of generation. The associated KMS key for this edition of Windows Server is the Windows Server 2008 Std/Ent KMS B key. However, that key will not enable the activation of operating systems from a later generation (Windows 7). Instead, you will need to use the corresponding Windows Server key for the latest generation to activate the products you need. That would be the Windows Server 2008R2 Std/Ent KMS B key. The KMS B key will activate a service that can activate these product groupings:

  • Server Group B for Windows Server 2008 R2, and

  • Server Group A for Windows Server 2008 R2, and

  • Client VL for Windows 7, and

  • Server Group B for Windows Server 2008, and

  • Server Group A for Windows Server 2008, and

  • Client VL for Windows Vista

The service activated with the Windows Server 2008R2 Std/Ent KMS B key will enable activation of systems running all of the operating systems contained within the product groupings in that bullet list. For some of you, that will raise the inevitable question, “what if I’m not licensed for Windows Server 2008 R2…can I still use this key to activate my KMS system?”. From a licensing perspective, no product should be used or deployed if licenses have not been purchased. If a volume license customer has Windows Server 2008 R2 KMS keys available due to purchase or evaluation rights, those KMS keys can be used to activate the service. It is important to note that not all Volume License customers will have access to these keys; it is dependent on the products purchased and the type of agreement. If the keys are not on the portal, there is no process or exception to get them.

From a product activation standpoint, there are actually two alternatives for this example: 1) use the Windows Server 2008R2 Std/Ent KMS B key on a single KMS system or 2) set up two distinct KMS systems (one enabled for Windows 7 using the Win 7 – KMS key and another for Windows Server 2008 using the Windows Server 2008 Std/Ent KMS B key). As stated above, the first alternative is acceptable from a licensing perspective as long as the key is available and any instances of Windows Server 2008 R2 that get activated are properly licensed. If Windows Server 2008 R2 is not deployed in the environment, but the key is available on the portal, the use of the key to activate the service does not require the purchase of any Windows Server 2008 R2 licenses. It is also important to reiterate here that not all Volume License customers will have access to all KMS keys, meaning that the second alternative may be the only choice. For more information on this, visit the Product Key FAQ on VLSC.

Choosing the KMS Key

If using KMS as your activation method, answer the following questions to pinpoint the “right” KMS key for your deployment. Think broadly when answer these questions, in terms of what you intend to deploy in the near future (e.g. within 6 - 12 months).

  1. Will you be deploying only Windows Client operating systems in the environment?

    1. No, go to 2.

    2. Yes

      1. For Windows 7 use the Win 7 – KMS key to activate the service on a designated host system

      2. For Windows 7 and Windows Vista use the Win 7 – KMS key to activate the service on a designated host system

      3. For Windows Vista use the Windows Vista - KMS key to activate the service on a designated host system

  2. What is the highest edition of Windows Server that you will deploy in the environment, with the Windows Client systems?

    1. Windows Web or HPC Server

      1. This is the KMS A key.

        1. Will Windows Server 2008 R2 be deployed?

          1. Yes, use the Windows Web Srv 2008R2 KMS A key to activate the service on a designated host system

          2. No, use the Windows Web/HPC Srv 2008 KMS A key to activate the service on a designated host system

          3. Note, if Windows 7 is deployed with Windows Server 2008, use the Windows Web Srv 2008R2 KMS A key to activate the service on a designated host system

    2. Windows Server Standard or Windows Server Enterprise

      1. This is the KMS B key.

        1. Will Windows Server 2008 R2 be deployed?

          1. Yes, use the Windows Server 2008R2 Std/Ent KMS B key to activate the service on a designated host system

          2. No, use the Windows Server 2008 Std/Ent KMS B key to activate the service on a designated host system

          3. Note, if Windows 7 is deployed with Windows Server 2008, use the Windows Server 2008R2 Std/Ent KMS B key to activate the service on a designated host system

    3. Windows Server Datacenter or Windows Server for Itanium-based Systems

      1. This is the KMS C key

        1. Will Windows Server 2008 R2 be deployed?

          1. Yes, use the Win Srv 2008 R2 Data Ctr/Itan KMS C key to activate the service on a designated host system

          2. No, use the Win Srv 2008 Data Ctr/Itan KMS C key to activate the service on a designated host system

          3. Note, if Windows 7 is deployed with Windows Server 2008, use the Win Srv 2008 R2 Data Ctr/Itan KMS C key to activate the service on a designated host system

Remember that not all Volume License customers will have access to all KMS keys (depending on the products purchased and evaluation rights granted by the agreement). This may necessitate the use of two KMS keys to activate different generations of Windows.

Multiple Activation Key (MAK)

The MAK keys are not automatically found in the Existing Keys section on the VLSC. Instead, the VLSC users need to request the MAK that they need by going to the New MAK Keys tab, which is found by hovering over the Product Keys page header. Once a MAK is requested it will appear on the Existing Keys web page along with all other Volume License product keys. Customers can request MAK keys on VLSC for each product grouping, corresponding to the products that they are entitled to per their Volume License agreement. The following screenshot shows VLSC for an internal Microsoft organization. Note that the key and organizational info has been blocked out to preserve confidential data.

image005

MAK keys are similar in behavior to retail keys, the difference being that they have more activations on them. The number of activations is dependent on the license agreement that you have purchased. There is not a 1:1 match with the amount of licenses purchased and the number of activations provided per key. In the screenshot above, the Win Srv 2008 Data/Itan MAK C key has 50 activations available (and has used 0). Unlike KMS, the MAK key is used to activate an individual system not a service. However, MAK does use the same product groupings as KMS. With MAK the activations are directly associated with a single product group and can only activate the Windows editions within that specific product group. Therefore, we say that MAK keys are lateral in nature.

image006

  • A MAK key is issued to and associated with a particular product grouping

  • Each MAK key will activate the products within that product group only

With MAK it is also important to know how the different generations of Windows work together. As I stated above, there are two sets of product groupings, one for the current generation of Windows (Windows 7 and Windows Server 2008 R2) and one for the previous generation (Windows Vista and Windows Server 2008).

  • Each MAK key will activate the products within that product group only

  • Each MAK key will only activate the products within a generation

As part of the deployment planning process, take a look at how many activations are provided for your MAK key(s). If more activations are needed, particularly if you plan not to use KMS or are using MAK for re-imaging, contact your local Microsoft Product Activation Call Center to request more activations be added to your MAK.

Examples

Let me run through a couple examples to illustrate this. Then in the next section (Choosing the MAK Key) you will find a simple questionnaire to determine the exact key that you need.

Example 1: Deploying Windows 7 and Windows Server 2008 Standard

In this scenario, you are deploying products from two distinct product groupings. You will need to request a MAK key for each of these product groupings on VLSC. Instructions on how to do this are available when you select the New MAK Keys option on VLSC. Request the Win 7 – MAK for Windows 7 editions and the Windows Server 2008 Std/Ent MAK B for Windows Server 2008 Standard.

Example 2: Deploying Windows Vista, Windows 7, Windows Server 2008 Standard, and Windows Web Server 2008 R2

This example has you deploying products from four distinct product groupings. Again, you will need to request a MAK key for each of these product groupings on VLSC. You will request the following MAK keys to activate these products:

  • Windows Vista – MAK

  • Win 7 – MAK

  • Windows Server 2008 Std/Ent MAK B

  • Windows Web Srv 2008R2 - MAK A

Choosing the MAK Key

Walk through the following questions to pinpoint the “right” key for your deployment. Think broadly when you answer these questions, in terms of what you intend to deploy in the near future (e.g. within 6 - 12 months).

  1. Will you be deploying only Windows Client operating systems in the environment?

    1. No, go to 2.

    2. Yes

      1. For Windows 7 use the Win 7 – MAK key to activate the individual systems

      2. For Windows Vista use the Windows Vista - MAK key to activate the individual systems

  2. What edition of Windows Server will you be deploying in the environment?

    1. Windows Web or HPC Server

      1. This is the MAK A key.

        1. For Windows Server 2008 R2 editions, use the Windows Web Srv 2008R2 - MAK A key to activate the KMS host system

        2. For Windows Server 2008 editions, use the Windows Web/HPC Srv 2008 MAK A key to activate the KMS host system

    2. Windows Server Standard or Windows Server Enterprise

      1. This is the MAK B key.

        1. For Windows Server 2008 R2 editions, use the Windows Server 2008R2 Std/Ent - MAK B key to activate the KMS host system

        2. For Windows Server 2008 editions, use the Windows Server 2008 Std/Ent MAK B key to activate the KMS host system

    3. Windows Server Datacenter or Windows Server for Itanium-based Systems

      1. This is the MAK C key.

        1. For Windows Server 2008 R2 editions, use the Win Srv 2008R2 Data Ctr/Itan MAK C key to activate the KMS host system

        2. For Windows Server 2008 editions, use the Win Srv 2008 Data Ctr/Itan MAK C key to activate the KMS host system

Conclusion

Hopefully, this document has helped you to understand the key types that exist for our Volume License customers and how to choose the right one for your needs. For more information on product keys and their use, visit the Volume Licensing site.