I’ve had to google this a few times, so I’ll blog the results here for future reference.
It’s possible to upgrade, for example, a Server 2008 R2 Standard server to Enterprise without rebuilding Windows. This is all covered in detail on the MS TechNet blogs.
The command to do so is:
DISM /online /Set-Edition:<edition ID> /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
To view what “editions” are available to upgrade to, do this:
DISM /online /Get-TargetEditions
I had issues using a valid VLSC key in this process. A comment by Brendan P of Microsoft explains why this is the case:
MAK keys map to multiple editions, so the underlying infrastructure doesn’t accept them. If you use the generic KMS client key, as Matthew suggests, that will allow you to proceed with the upgrade, and then you can either replace the key with a valid MAK post-upgrade or just use the KMS client key to activate against your internal KMS server.
The full list of KMS client keys can be found here on TechNet: technet.microsoft.com/…/ff793406.aspx
The command I ended up running to upgrade Server 2008 /w SP1 Standard (VL) to Enterprise was:
DISM /online /Set-Edition:ServerEnterprise /ProductKey:489J6-VHDMP-X63PK-3K798-CPX3Y
The successful run looks like this:
Deployment Image Servicing and Management tool
Version: 6.1.7600.16385 Image Version: 6.1.7600.16385 Starting to update components...
Starting to install product key...
Finished installing product key. Removing package Microsoft-Windows-ServerStandardEdition~blah [==========================100.0%==========================] Finished updating components. Starting to apply edition-specific settings...
Restart Windows to complete this operation.
Do you want to restart the computer now (Y/N)?