>Hi,
>
>I need to install MS .NET Framework 4.?? on customer server (Windows Server 2008 SP2). The server has .NET 3.5 installed.
>I found a link to download MS .NET Framework 4.5.2 (URL below) but it is not clear if this is update to Version 4.0 or can be installed on top of any version.
>http://www.microsoft.com/en-us/download/details.aspx?id=42643

Pretty sure that's all you need.

>Also, do you know if I will need to reboot the server after installing this .NET 4.??

Don't think so....