Erro .Net Framework 3.5 no Windows Server 2012

Como não sou usuário de Windows, ao tentar instalar o .Net Framework 3.5 server 2012 peguei o seguinte erro: Do you need to specify an alternative path? One or more instalation selections are missing source files on destination server. The server will try to get missing source files from Windows Update, or from a location that is specified by Group Policy. You can also click the "Specify an alternate source path" link on this page to provide a valid location for the source files.

Solução: Coloque o CD no drive e no prompt em modo administrador execute:

Add-WindowsFeature NET-Framework-Core -Source D:\sources\sxs

Pronto! Recomece a instalação do .Net Framework 3.5

Para maiores informações ou Windows 8 acesse: http://social.technet.microsoft.com/wiki/pt-br/contents/articles/12541.solucionando-problemas-erro-ao-instalar-o-net-framework-3-5-no-windows-server-2012-ou-windows-8.aspx