During the installation of Enterprise Console 4.5, the installation of the .net framework fails.Known to apply to the following Sophos product and version
Enterprise Console 4.5Operating System
Windows Server 2008 Essential Business Server
What to do
This problem occurred due to a known issue with this version of the Windows Operating System. More information is documented here:
Therefore, to resolve this issue, ensure that you have installed .NET Framework 3.5 SP1, read through the above Microsoft article, then re-install Enterprise Console 4.5.