Hmm probably glitch with compatibility with new RDP 6 protocol which was added for Vista and Server2003... maybe you could try forcing RDP 5 with the -5 command line option or even try forcing rdp 4 protocol with -4 ?

Might also try -E to disable encryption or -a 16 to force 16bit color (rdp 5 might have issue with alpha channel of vista?)

those are the first ones i'd try but you can type rdesk by itself to show all options.

This link seems to indicate the forcing 16 bit color would workaround
http://www.2x.com/forums/viewtopic.p...f1d27d7f3ec6ae