KMS Activating Windows 8.1 and Server 2012 R2

With each new release of Windows client and server operating systems nowadays, comes an update required to allow your on premise KMS host to activate those new operating system servers and clients using volume license activation.

After the general availability on Windows 8.1 Enterprise client and Windows Server 2012 R2, Microsoft released the update for KMS host for Windows Server 2008, 2008 R2 and 2012 to allow these down level operating systems to activate the latest and greatest.

You can get the download for the update from Installation of the update requires a KMS Host restart and you will need to obtain a new KMS Host key from your Microsoft Volume License Center account. Instructions for applying the new key with slmgr.vbs is given on the link above.

Windows 8.1 and Windows Server 2012 R2 use the KMS Client key by default after installation so you shouldn’t need to change anything to get your clients activated, but in case you need them, the KMS Client keys for all operating systems supporting KMS are available from


Richard works as a Cloud Consultant for Fordway Solution where his primary focus is to help customers understand, adopt and develop with Microsoft Azure, Office 365 and System Center. Richard Green is an IT Pro with over 15 years' of experience in all things Microsoft including System Center and Office 365. He has previously worked as a System Center consultant and as an internal solutions architect across many verticals. Outside of work, he loves motorbikes and is part of the orange army, marshaling for NGRRC, British Superbikes and MotoGP. He is also an Assistant Cub Scout Leader.