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Volume Activation Overview

Starting with the release of Windows Vista, Microsoft have changed Volume Activation. Products which fall under Volume Activation 2.0 require activation or they will not function.

Volume Activation is the only license method to allow imaging rights, so you need a volume license version to ghost or deploy Windows with images. If you are purchasing systems for use with the MCS then you can use the MCS image if you have a license for the same OS, i.e. MCS Vista Business requires a Vista Business license.

With Volume license versions available from software sales which fall under Volume License Activation 2 there are two ways of activating;

  • Multiple Activation Key (MAK)
  • Key Management Service (KMS)

MAK key activation

MAK keys are a limited use one time activation product key. Failure to activate the system within the grace period will result in continued warnings about the activation status. Once a system or product is activated it will not require further activation unless a major hardware change is made.

MAK key activations are most suitable for systems which will not be connected to the CUDN, i.e. portable devices, as systems with VL2 products require constant connectivity to the VL2 infrastructure to remain activated.

The Univeristy is provided with a limited number of MAK activations. Any activation depletes the pool of MAK activations we have.

KMS activation

KMS activation provides limitless activations for products. The KMS clients require periodic activation in a managed environment infrastructure. You can build your systems which will be imaged or re-installed with the KMS key and activate your systems in a managed manner.

While client systems require no additional activation maintenace once activated each system must periodically renew activation or revert to Reduced Functionality Mode.

A KMS server is activated with Microsoft and all client systems activate themselves with a local host.

In order for clients to find a KMS server they will use either DNS SRV records or be configured with group policy or registry settings to locate the server via name or IP address.

In order for the KMS server to start activating systems there is a minimum number of systems which must be available. For Windows desktop products this must be at least 25 clients, for Server and Office it is 5. Once this threshold has been reached systems will activate until the number of systems drops below 25.

Virtual machines can be activated with KMS, but do not count towards the 25 threshold.

KMS clients must periodically renew their activations with the KMS server. The renewal cycle for Windows desktop and server works as follows;

  • After installation Windows attempts to activate every two hours. There is a 30 day grace period for this to happen.
  • After activation Windows will attempt to renew activation every 7 days on a sliding 180 day window. After renewal the slider starts the 180 day count again.
  • If Windows cannot renew activation for 180 days it enters a 30 day grace period. During the grace period it attempts to activate every two hours.
  • If Windows cannot activate after this 30 days the Operating System will enter Reduced Functionality Mode (RFM) until it can connect to a KMS server or until you install a MAK key and activate on-line or by phone.

Requirements for KMS


KMS communicates over port 1688 TCP using RPC.

KMS requests and responses are a little over 200 bytes each and so you should not see any dramatic network traffic as a result of using KMS activation.

Imaging and Deployment

You should prepare your systems as normal for imaging, assuming you are using ghost or similar product.

Use sysprep to re-set the activation timers before ghosting to give you the full 30 day allowance before activation is required. Use generalise to do this. NOTE : You can only generalise a system three times, subsequent attempts to generalise and re-set the activation timers will fail.

If the system was activated before imaging using a MAK key, you need to convert it to use KMS.

Use the Slmgr.vbs script tool with the generic key to set a volume liscensed system to use KMS.

  • Cscript %SystemRoot%\System32\Slmgr.vbs -ipk <key>

Where <key> is the generic key supplied with Windows Vista, server 2003, 2003 R2 and 2008. The generic key can be found in \Sources\pid.txt on the install media.

Client Configuration

Slmgr.vbs is the configuration script provided with Windows for client and KMS server.

The main switchs for use are;

  • -ipk Install product key (used to replace MAK)
  • -dli Display license information
  • -ato Attempt immediate activation
  • -ckms Clear name of KMS computer used

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