The type of namespace 'administration' could not be found

Issue when you reference Microsoft.SharePoint.dll in Visual Studio 2010. If you’ve already put in the using statements like bellow:

using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;

You issue a build and it fails and you get the following message:
’The type of namespace 'administration' could not be found’

The fix: Change the target framework to .Net Framework 3.5 (Right click the project in visual studio and go to ‘Properties’)