Adding GUI to Server 2012 Core

Try this:

1. Import-Module Dism
2. Enable-WindowsOptionalFeature –online -Featurename ServerCore-FullServer,Server-Gui-Shell,Server-Gui-Mgmt
 
By the way, you can also try the following command line:
 
Dism /online /enable-feature /featurename:ServerCore-FullServer /featurename:Server-Gui-Shell /featurename:Server-Gui-Mgmt

Thank you for the quick response. The first command returns the following -

Enable-WindowsOptionalFeature : Feature name ServerCore-FullServer is unknown.
At line:1 char:1
+ Enable-WindowsOptionalFeature -online -Featurename
ServerCore-FullServer,Server- ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~
    + CategoryInfo          : NotSpecified: (:) [Enable-WindowsOptionalFeature
   ], COMException
    + FullyQualifiedErrorId : Microsoft.Dism.Commands.EnableWindowsOptionalFea
   tureCommand


and second gives -

PS C:\> Dism /online /enable-feature /featurename:ServerCore-FullServer /feature
name:Server-Gui-Shell /featurename:Server-Gui-Mgmt

Deployment Image Servicing and Management tool
Version: 6.3.9600.17031

Image Version: 6.3.9600.17031


Error: 0x800f080c

Feature name ServerCore-FullServer is unknown.
Feature name Server-Gui-Shell is unknown.
Feature name Server-Gui-Mgmt is unknown.
A Windows feature name was not recognized.
Use the /Get-Features option to find the name of the feature in the image and tr
y the command again.

The DISM log file can be found at C:\Windows\Logs\DISM\dism.log

Was this 2012 Standard? Datacenter?  You aren't trying to install the GUI on the free Hyper-V Server product, are you?

Its the same result but try it:
Install-WindowsFeature Server-Gui-Mgmt-Infra,Server-Gui-Shell

Check this from other blog maybe can be help.

Server features can be installed from the web via Windows Update. If you want to install from a local source, you can mount the install.wim file using Dism /Mount-Wim. When mounting the wim, make sure you mount an image index that contains the feature you want to install (e.g. Server with GUI). Then point Dism or Install-WindowsFeature to the mount directory (e.g. c:\mount) as the source.

The sxs directory on the media only contains files that are not already in the wim; that way you aren't downloading redundant data. Thus, if you wanted to install some feature like NetFx3 (.NET Framework 3.5), that feature is not included in any edition and is therefore not in the wim at all; you'd have to point to the sxs directory in this case.

If you wanted to create a centralized network install point that you could point to, you could extract the wim and then merge the contents of the sxs directory on the media with the winsxs directory in <mount>/windows/winsxs to have a single source that could install all features. Hope this makes sense! Let me know if you have any more questions or feedback about Features on Demand.

For more information, there is also documentation available at http://technet.microsoft.com/en-us/library/hh831786.aspx

Thank you Cliff, I didn't install this - have just been brought in to try and set up this box up to replicate a 2012 Standard server, so thought the first thing I would do is install GUI as not familiar with PowerShell.

Is there a way to check from Powershell / Command Prompt that this is Server 2012 Standard install ?

The command you seek is "winver" (without the quotes)

Had tried that but winver not recognized command (in command prompt or powershell)

winver isn't present in Hyper-V Server (but is included in a core install of standard or datacenter) so that's a *pretty* good indication that you aren't running core, but are running Hyper-V (free).

But if you really want to double check, "systeminfo" should report everything you need and *does* work in Hyper-V Server.
 
It spits back a ton of info though, including hardware and hotfix info. So piping it to "more" is a good idea.  systeminfo | more

And the first few lines will include the OS name and version.

Thank you - is this the free version - In which case I guess it cant be used to replicate a 2012R2 Standard Server ?

OS Name:                   Microsoft Hyper-V Server 2012 R2
OS Version:                6.3.9600 N/A Build 9600
OS Manufacturer:           Microsoft Corporation
OS Configuration:          Member Server
OS Build Type:             Multiprocessor Free
Registered Owner:          Windows User
Registered Organization:
Product ID:                06401-029-0000043-76293
Original Install Date:     13/08/2015, 15:49:24
System Boot Time:          12/10/2015, 13:02:53
System Manufacturer:       Intel Corporation
System Model:              S2600CP
System Type:               x64-based PC
Processor(s):              1 Processor(s) Installed.
                           [01]: Intel64 Family 6 Model 45 Stepping 7 GenuineInt
el ~2494 Mhz
BIOS Version:              Intel Corp. SE5C600.86B.02.05.0004.051120151007, 11/0
5/2015