If there are multiple subkeys, verify which one is the product you are interested in changing, it may be Office, Visio, and so on.
Use regeidt to locate the following registry subkey or something similar. Note: I had not attempted this edit on the 32-bit system. These steps require the use of regedit and differ from the 32 bit OS to the 64 bit OS.
Such examples may be changing from a retail key to a volume license key or vice versa or to remove the license on a computer that you are selling, this would require the enduser to supply their appropriately purchased license key. There are many situations that come to mind as to the reason why someone would want to change the product key.
