PC computer manufacturers include a single license of the Windows operating systems with the machines that they distribute. These licenses of Windows are considered Original Equipment Manufacturer copies, or OEM, since they will work with only the original computer. If your organisation or company decides to purchase volume licensing of Windows, you can deactivate the OEM copy and convert computers to the new volume licensing copy instead.
Log on to the computer as an administrator, hold down the Windows key and the "R" key at the same time and then enter "regedit" into the dialogue box that appears.
Navigate to the HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\Current Version\WPAEvents directory in the registry.
Right-click on the item labelled "ODBETimer" and choose the "Modify" option.
Delete any character in the item's value and replace it with a number from 0 to 9 or a letter from A to F.
Press "OK" and close the Registry Editor tool.
Hold down the Windows and "R" keys again and run the "%systemroot%\system32\oobe\msoobe /a" command in the dialogue box.
Select the "Yes, I want to telephone a customer service representative to activate Windows" option and press "Next."
Click on "Change Product key," enter the volume licensing product key in the appropriate field and then hit "Update."
Restart the computer to begin using the new volume licensing product key.