Update: This post was made in 2013 (5 years ago at time of writing). It’s clear from the many comments it sometimes works and sometimes doesn’t, and I suspect Microsoft may have broken it with various different install builds, or it just didn’t work with certain releases and configurations. Most recently, I installed a full copy of Win 2012 on a new server (using official Open License ISO media), it didn’t ask me for a license code on install, and then when I tried to use the below method (post install) it wouldn’t work – thanks MS!
I believe I found that using the following command from the cmd prompt did the trick:
It allowed me to replace the 25 digit generic / trial code MS had installed the OS with with my proper license key. If you type in the above and hit enter, it should give you all the available parameters to try and achieve what you want. No idea if it will let you apply an OEM or retail key to an Open License install, etc! Good luck :-)
So I’m at the end of the trial period for Windows Server 2012, and having a bought a volume license for the Data Center edition, I need to activate it. Microsoft have taken away the ability to alter product keys through Control Panel -> System so we have to use the command line.
I’ve read a lot of articles out there on this, which generally don’t work, presenting an error when you try and process your new key using the slmgr command line tool.
First of all, you need to establish your exact currently installed version. From a elevated command prompt, run the following command:
DISM /online /Get-CurrentEdition
In amongst the blurb that appears on screen, it will tell you your current edition (in my case ServerDatacenterEval). Make a note of this – you will use in the next command with the last ‘Eval’ bit ommitted.
With your license key to hand, now run following command:
DISM /online /Set-Edition:ServerDatacenter /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /AcceptEula
The above unboldened / italicised entries will need to be your own specific variables (remember to drop the ‘Eval’ bit for the Set-Edition). I believe, you can also use this as an opportunity to upgrade to a higher edition, for example using the /Set-Edition switch to go from Standard up to Datacenter. The /AcceptEula switch allows the system to silently accept the Microsoft license agreement.
When you run this command, your system will need to restart 1 or 2 times. Thereafter (if it doesn’t happen automatically) you will be able to activate with your newly provided key from Control Panel -> System or using the slmgr tool, and you will now be running your licensed copy :)