Windows Vista and Remote Desktop

I have been connecting via VPN in Windows XP and using Remote Desktop in
Windows XP for years and now have a notebook that has Windows Vista and am
having trouble connecting to the same Windows XP Pro workstation in my
office. I am able to create the VPN connection and can ping the IP address
of the Windows XP workstation I would like to connect via RDP, but when I try
and take control of the XP workstation using the Vista PC via RDP, the screen
goes blank and then after a period of a few minutes gives an error that the
connection can not be made and to consult an administrator. I am certain I
am trying to connect to the XP host because I get the following message in
the event log of the XP machine "the rdp protocol component x224 detected an
error in the protocol stream and has disconnected the client" I hope someone
has advice and I thank all in the discussion group for your thoughts in
advance. Regards, Mike Wortel