Hello, I have created a new Master Image and since then my clients no longer keep their GUIDs during refresh. I must have made some change that causes this. Before I start rolling back my latest changes and recreating images I just wanted to check if anyone had similar issues, and which logs to check for troubleshooting. These are the changes made before creating the latest image... I do patching during image build Added a SLP Added SMSSLP=<server> to the Setup ConfigMgr step in Capture Task Sequence Added the Install Updates step (It installs all Windows updates to date) Partitioning I now create two partitions in the Build/capture Task Sequence as well as in the Install-TS. I capture them and in the Install-TS apply index 2-2 to OSPART. Previosly I only created one partition in the Capture-TS. I also increased the boot partition to 300MB. VMware ESX was upgraded to 4.x (VM is used as build/capture-machine) VMware Virtual Machine Version is now 7, was 4 NIC is now VMware vmxnet3, was Emulated Intel e1000 SCSI Controller is now Virtual LSI Logic SAS, was LSI Logic Parallel

I've narrowed it down to not being caused by Partitioning or VMware Version. I also tried specifying SMSSLP=<server> in the capture Task Sequence without actually installing any updates in a later step. This doesn't cause the problem to occur either (the client keep its GUID on refresh). Could it be that one of the 45 updates (like .NET Framework 4) is doing post-install work during the sysprep phase, or some other timing-issue. The problems doesn't seem to be the updates themselves. If I install an image without update, patch it, and then do a refresh the problem doesn't occur. Only when they are sealed into the Master Image.

The issue disappear when I remove ".NET Framework 4.0 Client Profile" from the update package that runs during my capture-TS. I'm gonna try to instead add the full .NET Framework 4 package and see if the result is any different. Please continue following my blog :)

This might be an issue specific to my environment by anyway... capturing an image with the full .NET Framework 4 instead of Client Profile solves the problem for me. No new GUID during client refresh.