slmgr.vbs /rearm does not reset the guid
Posted on 2012-03-21
Many of my client PCs are getting 'activation failed' after months of being installed and working fine. I checked my KMS server and its only reporting a count of 16, well under the minimum of 25. So my next step was to find out why it only counts 16 when i have over 40 Win7 clients, and of course it is because many of our computers have duplicate GUID numbers, I verified this from the KMS event log. Apparently, when these computers were imaged they were not sysprepped at all. So now my task is to reset the GUID numbers on all the computers using slmgr.vbs /rearm and this is where my problem is. When I run the command, nothing happens, the GUID stays the same and I cannot figure out why.
I find many articles explaining the relationship between slmgr.vbs /rearm and the skiprearm key in the registry. The key did not exist at all, probably because sysprep was never run. I tried running rearm without the registry key and I also tried creating the registry key and running rearm again. No luck, when I check the KMS event log this computer is still using the same GUID.
I am aware that Microsoft does not support the rearm command being used in this scenario, they will ask me to sysprep the image properly and then reimage all of the computers. That's great, I want to do that, but reimaging 30 or more computers is simply not feasible, we're talking many days of work and delays to our workers.
Does anyone know how to get the GUID changed on these computers?