Server Core to Gui Error: "The source files could not be found."

I had installed base Windows Server 2012 Core to a virtual machine and tried to upgrade it to the GUI version.  Had a crazy error:

 0x800f0906 or ‘the source files could not be downloaded’ error

My machine was not on the network and I had the install CD.  I could not get it to install at all.  Did some digging and found that the following will work.
Be sure to include the colon ":" after the word '-Source' and after the 'WIM' tag for the source location.   Knowing the correct index in the install WIM is important as well.


First, confirm your edition index in install.wim:
dism /get-wiminfo /wimfile:d:\sources\install.wim

Index:1 Windows Server 2012 SERVERSTANDARDCORE
Index:2 Windows Server 2012 SERVERSTANDARD
Index:3 Windows Server 2012 SERVERDATACENTERCORE
Index:4 Windows Server 2012 SERVERDATACENTER

It will produce Win Server 2012 R2 SERVERSTANDARD as index 2, then:
Intall-WindowsFeature Server-Gui-Mgmt-Infra -Source:wim:d:\sources\install.wim:2

The last number is the edition index, change to 4 if running in SERVERDATACENTERCORE.


Using the Dism command works as well, but it is a longer process, since you have to mount the WIM file.



USING A SHARE NAME from an existing machine:
Dism /Online /Enable-Feature /FeatureName:Server-Gui-Mgmt /All /Source:\\[serverfqdn]\c$\Windows\WinSxS /LimitAccess