While installing .NET Framework 3.0 on Windows Server 2008, if you face the following error:

You must use the Role Management Tool to install or configure Microsoft .NET Framework 3.0
Please refer to the steps to install .NET Framework 3.0 on Windows 2008 through Server Manager:

1. Login to the Windows 2008 Server.
2. Click on Start >> All Programs >> Administrative Tools >> Server Manager.
3. Under Server Manager >> Features, click on Add Features.
4. From the Add Features Wizard, select the Features you want to install on the server.
5. Check box the option of .NET Framework 3.0 Features, click Next.

6. You will have to Confirm Installation Selections and click on Install.
7. .NET Framework 3.0 will be installed on the server.

Windows Support Department