Don't remove the .NET framework from Windows Server 2012. I hope you are not aware that this is the part of Windows Server 2012 and if you uninstall it, it will remove from your computer and when your computer will start, you will not get your Windows GUI interface. It will show you only command prompt.
I have done the same mistake, I removed .Net framework and my windows stop working. I tried many things to re-install .net framework but failed.
I was searching for the solution then i got the complete solution at only one website. Everywhere is half of the solution mentioned.
If you also want to give it a try, just remove .net from Server 2012. You window will not work and you will have to follow step by step below instructions to get it back.
How to Re-Install GUI after .net Uninstallation on Windows Server 2012