Returns a list of the default options excluding options that cannot be performed.
The SMTP Port (normally 25) must be open to do a SMTP connect or mailbox check. Must be connected to the
internet to do an MxRecord lookup. This effectively performs the greatest possible
validation depending on the local machines connection capabilities.
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2