Occasionally we have an issue with Office 2010 not activating with our Office KMS activation server.
Here are the key steps we take to get it working quickly again from the client side. I'm assuming that the KMS server is working correctly.
The lines are run from the command prompt. You need to start the command prompt with admin rights or you will get access denied errors.
1. Make sure the time and timezone is set correctly on the client machine. If the time is off by a lot it will not activate.
(Type cmd in the search bar to locate the command window, Right click on cmd and click Run as administrator from the context menu, or select cmd and hit CTRL-SHIFT-ENTER on the keyboard. ◦Click Yes at the User Account Control prompt to open the command window with elevated privileges)
3. At the command prompt, change to the Office14 folder (this is where the ospp.vbs script is located by default)
cd \Program Files\Microsoft Office\Office14\
4. You could start with manually trying to activate Office to see if the resulting error message is helpful for troubleshooting. At the command prompt type:
cscript ospp.vbs /act
5. Run this command to manually specify the IP address of your Office KMS Server.
cscript ospp.vbs /sethst:10.80.0.8 (Use the IP address of your Office KMS Server)
4. Run this command to activate Office with the KMS server:
cscript ospp.vbs /act
More in-depth troubleshooting ideas can be found here if the above doesn't work for you
http://blogs.technet.com/b/office2010/archive/2009/12/18/volume-activation-tips-and-tricks.aspx