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Hello, my name is Scott McArthur. I am a Senior Support Escalation Manager in the Windows group and today’s blog will cover KMS volume Activation.
With Windows Vista we introduced 2 methods for activating volume license versions of Windows. Key Management Service (KMS) and Multiple Activation Key (MAK). KMS keys are grouped to activate different sku’s of Windows. See KMS Host Keys to Products Activated for more information. I am going to discuss one of the most common issues we see in support about KMS activation.
When you try to activate a computer you receive the following error code: 0xC004C008. This error code means the following:
The activation server determined that the specified product key could not be used.
The Key Management Service (KMS) key has exceeded the activation limit.
KMS keys will activate up to 10 times on six different computers. If more activations are necessary, contact the PA Call Center.
The common issue we see in support is that customers will use their KMS host key to activate individual KMS clients. With Windows XP/2003 a volume license key was used on each computer when you install. So when you apply this same process to Windows Vista, Windows Server 2008, Windows 7, or Windows Server 2008 R2 you will encounter this issue.
The KMS host key should only be installed on your KMS host. The key allows for 6 activations on different hardware and 10 activations on the same hardware. This is so that you can rebuild your KMS host or move the KMS Host functionality to a new system. Everything will appear to work until you reach that seventh activation.
Correct Steps for setting up KMS host and KMS clients.
Note: These are the basic steps. For additional information see the Additional Resources at the end of this blog.
1. Select a computer that you want to be your KMS host.
2. Windows Vista, Windows 7, Windows Server 2008, Windows Server 2008R2, and Windows Server 2003 can be KMS hosts. Which OS you should use depends on a number of factors. Generally we would recommend either Windows Server 2003 or Windows Server 2008R2 so that your KMS host can support Office 2010 activation in the future. Install the Operating system from volume license media. You should not be prompted for a cdkey
At cmd prompt type the following
Slmgr.vbs /ipk <KMS host key>
The /ipk installs the key. Note if you need to change your key. For example change from a KMS_B to KMS_C key you must restart the SLSVC service (Vista/2008) or SPPSVC(Win7/R2).
The /ato activates the computer. You must activate the KMS host
4. Install the KMS client computers by using volume license media. You should not be prompted for productkey during installation
5. By default these KMS client computers will query DNS and locate your KMS host and activate
KMS Host key: This is the key that you obtain from Microsoft for your contract
KMS Host: This is the computer that you have designated as your KMS host
KMS Client: This can be Windows Vista, Windows Server 2008, Windows 7, or Windows Server 2008 R2 computers that you are trying to activate by using KMS.
1. First, you must have your KMS Host limit increased so that it can support additional activations. For information about how to reset your KMS key see the following document:
MAK and KMS Volume License Keys and Their Activation Limits:
2. Identify those computers that were incorrectly activated by using the KMS host key which in turn has turned those computers into KMS hosts. The easiest method is to run the following command to output VLMCS DNS records
nslookup -type=all _vlmcs._tcp>kms.txt
If you goto these individual machines you double check this by running the following command
I have highlighted some important information in this output. If you see “Key Management Service is enabled” then you know this computer is a KMS host. You can also see the channel of the key that was used to activate the computer. In this example the KMS_C key was used. See KMS Host Keys to Products Activated for information on the different types of keys. The partial product key is also very useful to determine what specific key was used.
3. Re-establish computers as KMS clients either using VAMT remotely or manually on the device itself.
If you have administrative rights to the computers and the computers have WMI enabled in the firewall then it is possible to use the VAMT 2.0 tool to reset these computers remotely.
A. Download and install the VAMT 2.0 tool B. In VAMT console click “All products” C. Enter the computername or IP address D. Right click the computer and choose “Update status” E. Right click the computer and choose “Install Product Key” F. Click “Install a KMS client Key”. Note: This is installing the KMS Client Setup Key
A. Download and install the VAMT 2.0 tool
B. In VAMT console click “All products”
C. Enter the computername or IP address
D. Right click the computer and choose “Update status”
E. Right click the computer and choose “Install Product Key”
F. Click “Install a KMS client Key”. Note: This is installing the KMS Client Setup Key
Once the device shows the key type as ‘GVLK’, then it has re-established itself as a KMS Client.
If you cannot use VAMT 2.0 you can also reset these machines back to KMS clients manually by logging on to them. Type the following at elevated command prompt
Slmgr.vbs /ipk xxxxx-xxxxx-xxxxx-xxxxx-xxxxx
Where xxxxx-xxxxx-xxxxx-xxxxx-xxxxx is the KMS Client Setup Key for the edition installed. This will make these computers be KMS clients and look for a KMS host.
4. In order for this change to can either reboot the computer or restart the licensing service
Windows Vista/2008(Software Licensing)
Net stop slsvc
Net start slsvc
Windows 7/Windows Server 2008R2 (Software Protection)
Net stop sppsvc
Net start sppsvc
Note: If you don’t restart or reboot the computer may continue to register itself in DNS as KMS host
A KMS client will look like this. I have highlighted some important information. You can see that this is a Volume_KMSCLIENT Channel. You can see it is using the default key. See KMS Client Setup Key for the default keys. You can also see what KMS host has activated the machine.
5. Open Microsoft DNS MMC or your 3rd party DNS management tool
6. Using the nslookup output as reference locate srv records for those machines that were incorrectly setup as KMS hosts. For example you can see 2 KMS hosts listed in this output (2008KMS and 2003KMS)
7. Delete the records for those computers that were incorrectly setup as KMS hosts so only your approved KMS hosts are listed.
Note: To prevent this from occurring in the future you can create a security group that contains your approved KMS host computers and set permissions on the _VLMCS record so only that group can update it.
Volume Activation Portal: http://technet.microsoft.com/en-us/windows/dd197314.aspx
How to troubleshoot Volume Activation error codes on Windows 7, Windows Server 2008 and Windows Vista-based computers
MAK and KMS Volume License Keys and Their Activation Limits
Top 5 Product Key Activation Challenges IT Pros Encountered and Solved
Microsoft Activation Centers Worldwide Telephone Numbers
KMS Client Setup Keys
Operating system edition
Windows 7 and Windows Server 2008 R2
Windows 7 Professional
Windows 7 Professional N
Windows 7 Professional E
Windows 7 Enterprise
Windows 7 Enterprise N
Windows 7 Enterprise E
Windows Server 2008 R2 Web
Windows Server 2008 R2 HPC edition
Windows Server 2008 R2 Standard
Windows Server 2008 R2 Enterprise
Windows Server 2008 R2 Datacenter
Windows Server 2008 R2 for Itanium-based Systems
Windows Vista and Windows Server 2008
Windows Vista Business
Windows Vista Business N
Windows Vista Enterprise
Windows Vista Enterprise N
Windows Web Server 2008
Windows Server 2008 Standard
Windows Server 2008 Standard without Hyper-V
Windows Server 2008 Enterprise
Windows Server 2008 Enterprise without Hyper-V
Windows Server 2008 HPC
Windows Server 2008 Datacenter
Windows Server 2008 Datacenter without Hyper-V
Windows Server 2008 for Itanium-Based Systems
KMS Host Keys to Products Activated
Volume product group
Products activated by key type
Windows Vista Enterprise
Windows 7 Enterprise
Windows Server 2008 R2
Server Group A:
Windows Web Server® 2008 R2
Windows Server 2008 R2 HPC Edition
Windows HPC Server 2008 R2
Windows Server 2008 R2 Group A
Windows Server 2008 Group A
Windows Vista Volume Editions
Windows 7 Volume Editions
Server Group B
Windows Server 2008 R2 Enterprise
Windows Server 2008 R2 Group B
Windows Server 2008 Group B
Server Group C
Windows Server 2008 R2 for Itanium-Based Systems
Windows Server 2008 R2 Group C
Windows Server 2008 Group C
Scott McArthur Senior Support Escalation Engineer Microsoft Enterprise Platforms Support
If we already installed server 2008 using non VL media, can we convert our machines to KMS clients without re-installing? I tried simply putting in the KMS key using slmgr but all that did was make the machines KMS hosts - ack.
Scott, I believe the slmgr.vbs command options are preceded by a "/" rather than a "-"
e.g., slmgr.vbs /ipk xxxxx-xxxxx-xxxxx-xxxxx-xxxxx
Dashes and slashes both work.
This is absolutely ridiculous! I understand Anti-Piracy and security requirements, but Microsoft have totally ignored usability!
This is a VERY poor solution to say the least!!
I am not using a host. I purchased my copy through the MS agreement with our college's faculty and staff. I updated my pc from windows 7 home edition to windows 7 pro. That worked fine. So, when I purchased a laptop to use at meetings, I tried to do the same. It didn.t work at all, so I did a full install from my disk. Now I am getting this error. This is so infuriating!!! I am not an IT professional, so this article makes no sense to me at all. What can I do?
You saved me!!!