Can't install .Net framework 3.5

Question

I downloaded .Net framework 3.5.1 sp1 on windows server 2008 R2, 64 bit OS and every time i run the exe file i got an error message

"You must use the Role Management Tool to install or configure Microsoft .NET Framework 3.5 SP1" .

I started the Server Manager selecting the Features node and "Add Features" and enabled .net framework features but the error still occurred .

Answer 1

Please see How to install/enable .Net 3.5 SP1 on Windows Server 2008 R2 for SQL Server 2008 and SQL Server 2008 R2