First things first;
http://www.microsoft.com/downloads/details.aspx?FamilyID=bbf2eb61-2b30-4f2d-bccd-df53e220b8e9&displaylang=en
This is a great intro video to KMS’ing on a Win 2008 box, it will cover all the basics and give you a good idea on how this works.

You likely need this patch to upgrade the KMS service on the Win 2008/2003 box to allow Win7 etc. to register;
http://support.microsoft.com/kb/968912 – for Win 2008 kms
http://support.microsoft.com/kb/968915- for Win 2003 kms

Now you will need to add a KMS key to the server you got this key from Microsoft as part of your license (NOT a MAK key, a KMS key).. This might confuse you as it did me, I was thinking, oh I will need to add KMS keys for all the versions of windows I need the KMS to work for, but this is not so..

On this page;
http://www.microsoft.com/downloads/details.aspx?FamilyID=9893f83e-c8a5-4475-b025-66c6b38b46e3&displaylang=en
you will find a document “Volume Activation 2 0 Changes for Windows Server 2008 and Windows Vista SP1.doc” explaining this in more detail, but basically if you install a server 2008 R2 KMS key then this will also work for Win7, Vista etc.

How do i register a key on the KMS server;
Start an elevated CMD.exe and
change dir to c:\windows\system32

write: slmgr -IPK <YOUR KMS KEY HERE>
wait for a confirmation dialogbox, this can take a long time up to 1 min or more..
then activate the KMS key: slmgr -ATO
wait for a confirmation dialogbox, this can take a long time up to 1 min or more..
Now check the status of the KMS server: cscript slmgr.vbs -dlv
It will take a while before it is displayed.

Damn if I understand why there is no GUI for this!?

FAQ;
Help, I have machines registered with a MAK key, and now want to change this to my new KMS server – how do I do this? It is not that complicated, all you need to do is to change the license key of the workstation/officepack to a KMS key, IMPORTANT!! we are NOT talking YOUR KMS KEY, but the default KMS key from MS – confused!!? I was too, well it is not that complicated when it comes to it, when you install a MVLS product like eg. Office 2010 then it carries a default key this is the default KMS key with a limited lifespan, once you click activate this key tells the product to seek out a KMS server and try to register – if no KMS server is found the activation fails.  If you entered a MAK key at the time of installation then the product is activated and you need to unactivate it with the KMS key for that product, a list of default KMS keys can be found here;
http://technet.microsoft.com/en-us/library/dd772269.aspx#EOIAC

Operating System Edition  Product Key

Windows 7 Professional -  FJ82H-XT6CR-J8D7P-XQJJ2-GPDD4
Windows 7 Professional N -  MRPKT-YTG23-K7D7T-X2JMM-QY7MG
Windows 7 Enterprise -  33PXH-7Y6KF-2VJC9-XBBR8-HVTHH
Windows 7 Enterprise N – YDRBP-3D83W-TY26F-D46B2-XCKRJ
Windows 7 Enterprise E – C29WB-22CC8-VJ326-GHFJW-H9DH4
Windows Server 2008 R2 HPC Edition -  FKJQ8-TMCVP-FRMR7-4WR42-3JCD7
Windows Server 2008 R2 Datacenter -  74YFP-3QFB3-KQT8W-PMXWJ-7M648
Windows Server 2008 R2 Enterprise – 489J6-VHDMP-X63PK-3K798-CPX3Y
Windows Server 2008 R2 for Itanium-Based Systems -  GT63C-RJFQ3-4GMB6-BRFB9-CB83V
Windows Server 2008 R2 Standard – YC6KT-GKW9T-YTKYR-T4X34-R7VHC
Windows Web Server 2008 R2 – 6TPJF-RBVHG-WBW2R-86QPH-6RTM4
Windows Vista Business   YFKBB-PQJJV-G996G-VWGXY-2V3X8
Windows Vista Business N    HMBQG-8H2RH-C77VX-27R82-VMQBT 
Windows Vista Enterprise    VKK3X-68KWM-X2YGT-QR4M6-4BWMV 
Windows Vista Enterprise N    VTC42-BM838-43QHV-84HX6-XJXKV
Windows Server 2008  Datacenter    7M67G-PC374-GR742-YH8V4-TCBY3 
Windows Server 2008 Datacenter without Hyper-V     22XQ2-VRXRG-P8D42-K34TD-G3QQC 
Windows Server 2008 for Itanium-Based Systems      4DWFP-JF3DJ-B7DTH-78FJB-PDRHK 
Windows Server 2008 Enterprise    YQGMW-MPWTJ-34KDK-48M3W-X4Q6V 
Windows Server 2008 Enterprise without Hyper-V     39BXF-X8Q23-P2WWT-38T2F-G3FPG 
Windows Server 2008 Standard  TM24T-X9RMF-VWXK6-X8JC9-BFGM2 
Windows Server 2008 Standard without Hyper-V     W7VD6-7JFBR-RX26B-YKQ3Y-6FFFJ 
Windows Web Server 2008    WYR28-R7TFJ-3X2YQ-YCY4H-M249D
Microsoft Office 2010 – VYBBJ-TRJPB-QFQRF-QFT4D-H3GVB

You can change the license key via this command (remember it has to be launched from an Elevated CMD.exe);
cscript Slmgr.vbs /ipk <SetupKey, the key from above>

Advanced tips and tricks;
Use other than the default KMS server (force a specific KMS server)
If for some reason you need to specify WHICH KMS server you wish to use (or if you need to use a remote KMS) then you do like this;
1. open an elevated cmd.exe
2  type; cscript slmgr.vbs -ipk <KMS KEY (not your own, one of the default microsoft once>
3  type; cscript slmgr.vbs -skms <IP OF KMS SERVER>:<PORT NO On KMS SERVER>  (default port is 1688)
4  type; cscript slmgr.vbs -ato

Command lines;
cscript slmgr.vbs -dlv (show status of KMS)
cscript slmgr.vbs -dli (show quick status of KMS)
cscript slmgr.vbs -dlv all (show advanced status of KMS)
cscript slmgr.vbs -upk (Remove key – unactivate Windows CAUTION!! – this may however be needed if you wish to remove the KMS role from a server)

Upgrade your KMS to accept Office 2010 clients;
Microsoft Office 2010 KMS Host License Pack
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=97b7b710-6831-4ce5-9ff5-fdc21fe8d965
IMPORTANT! Strangely enough this is NOT supported for Windows 2008 KMS servers, it works for 2003, 2008 R2 but NOT 2008. (more here; http://social.technet.microsoft.com/Forums/en-US/officevolact/thread/b2ffee91-c6a4-4196-8a86-4974534c3dbd)

Error codes;
If you get an errorcode; Error: 0xC004F015
This may indicate that you are trying to import a KMS key that is already covered, eg. you installed a KMS key for servers KMS_B key and are trying to install a KMS for Windows7 then this Errorcode will be shown – Windows 7 is already covered by your KMS_B server key (yeah strange I agree, but that is how it works)..
(more here; http://www.vistax64.com/vista-installation-setup/173686-setup-kms-2k8.html)

Stop the KMS server (stop the KMS service on a machine);
open a commandprompt (elevated);
type; net stop slsvc – to stop the service
type; net start slsvc – to run it again

Check that the DNS records are created properly;
open a commandprompt (elevated);
type; nslookup -type=srv _vlmcs._tcp

you should see something similar to this:

_vlmcs._tcp.domain.net SRV service location:
priority = 0
weight = 0
port = 1688
svr hostname = kmsserver.domain.net
kmsserver.domain.net internet address = x.x.x.x
General tips and tricks;
http://technet.microsoft.com/en-us/library/dd996588.aspx

Volume Activation Technical Reference Guide (very useful)
http://technet.microsoft.com/en-us/library/ee355153.aspx

in the technical reference guide you can among other thing find this;

Customizable Activation Help

For product activation in managed environments, the Activate Windows now dialog box can be configured to display an optional Learn About Activation Online link, as shown in Figure 4.

Figure 4 Learn about activation online

Clicking this custom link loads an administrator-defined URL in the user’s default browser. This URL can point to a custom Web page or other file stored on the local computer or on a network share. A Volume Licensing customer can use this link to direct their users to the customer’s Helpdesk or other activation-related resources. Displaying the link requires setting the REG_SZ value AlternateURL to the URL of the Web page to display when the user clicks it. The value AlternateURL is in the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\CurrentVersion\SoftwareProtectionPlatform\ACTIVATION registry subkey.

LINKS

Tools to configure client computers in Office 2010

Configure and deploy volume activation of Office 2010

How to troubleshoot Volume Activation error codes on Windows 7, Windows Server 2008 and Windows Vista-based computers

Volume Activation Tips and Tricks

Microsoft Office 2010 Beta Key Management Services (KMS) Host Setup

Office 2010 KMS Aktivierung (German, but with pictures

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Links

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