Server
2008 R2: “You must use the Role Management Tool to install or configure Microsoft .NET”

By Jason on
March 15, 2011

I was trying to install an application on a VM running Server 2008 R2. The program required Microsoft’s .NET Framework 3.5 SP1 and wouldn’t install without it. Oddly, Windows Updates was installing updates for .NET Framework 3.5 and installing .NET Framework
4 didn’t work either. I tried downloading the
.NET Framework 3.5 Service Pack 1 but when I ran the installer, I received this message: “You must use the Role Management Tool to install or configure Microsoft .NET Framework 3.5 SP1.”

This is because Windows 2008 R2 ships with the .NET 3.5.1 framework. You just need to enable the feature from
Server Manager.

装了之后再 装framework 就ok了