Microsoft .NET Framework could not be installed in Windows Server operating system using the CustomTools pre-requisites installer. In Windows Server, the .NET Framework could be installed from the Windows Server Management instead.
You can find the Microsoft .NET Framework v4.5 installation option from the Add Features feature in the Windows Server Manager. See the following links for the further instructions:
| Windows Server 2008 R2 | Adding Server Roles and Features |
| Windows Server 2012 |
Install or Uninstall Roles, Role Services, or Features
Server Roles and Technologies in Windows Server 2012 |