Here is a way to disable that auto send read receipt feature in Outlook 2007.  There is a registry key created when this is turned on. It’s located at HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Preferences\ReadReceipt  it’s a DWORD value of 00000001 when it is turned on.  To change this, just have a login script rewrite this value to all zeros [...]