Install .NET Framework 3.5.1 on all of the Windows servers, logged on as a user who is a member of the Administrators group.
If the .NET Framework software is missing, a prerequisite check causes the installation or upgrade program to exit.
Follow these steps:
Run the following command (if firewall permits):
>dism.exe /online /enable-feature /featurename:NetFX3 /all
Note: The above command may not work in all environments, in which case you will need to install .NET through side-by-side installation with the Windows install disc. These steps are captured in the following section.