Remote desktop sessions do not completely exit, and you cannot establish new remote desktop sessions to a computer that is running Windows Server 2008 R2

http://support.microsoft.com/kb/2383928

KB Article Number(s): 2383928
Language: All (Global)
Platform: x64
Location: (http://hotfixv4.microsoft.com/Windows%207/WindowsServer%202008%20R2/sp1/Fix325177/7600/free/419078_intl_x64_zip.exe)