Windows 2012 Server: Enable .NET 3.5

Question

I have a Windows 2012 Server which needs .NET 3.5 installed. For background info/solutions, please see this: http://sqlblog.com/blogs/sergio_govoni/archive/2013/07/13/how-to-install-netfx3-on-windows-server-2012-required-by-sql-server-2012.aspx

I have tried this but it doesn't work for me. Here is what I am trying: Using a Windows 2012 ISO file, 'mount' on the 2012 Server as 'D' drive and then tried both GUI and Command prompt. In case of GUI, I specified the 'alternate source' path to the D drive's 'source/sxs folder but that failed without giving enough info.

In case of the command prompt, here is what's happening:

dism /online /enable-feature /featurename:NetFx3  /source:d:\sources\sxs

I get error: Installed but Parent feature not enabled. So I tried another approached:

dism /online /enable-feature /featurename:NetFx3  /all /source:d:\sources\sxs

the above command, per http://blogs.technet.com/b/askcore/archive/2012/05/14/windows-8-and-net-framework-3-5.aspx is supposed to enable parent elements; but running this I get error like 'source not found'.

Is there some error in my second command? What else I could do?

This is Windows 2012 Server Standard edition.

Thanks!

Solution 1

Never mind. It turned out that I needed a 'Windows Server 2012 R2' ISO because that's what the target server was; I was trying to a regular 'Windows Server 2012' ISO and that was throwing the 'source not found' error. I downloaded an 'eval' copy of the R2 ISO from Microsoft site, 'mounted' it on the target server and, voila, the following command ran fine and now .NET 3.5 is enabled!

Thanks!

dism /online /enable-feature /featurename:NetFx3  /all /source:d:\sources\sxs

Solution 2

See also this answer which indicates if you have a Language Pack installed you may need to uninstall it, restart, and retry.