Just to let you know Exchange 2010 Ru4 has been pulled from the Download Centre.

This is due to an issue , where by moving or copying a folder via an outlook client actually deletes subfolder and content in the folder.

Microsoft are going to be sorting this issue in the next Exchange Rollup ( RU5 ) which is due for release around August.

For more information please see http://blogs.technet.com/b/exchange/archive/2011/07/13/exchange-2010-sp1-ru4-removed-from-download-center.aspx