I have managed to get Remote Assistance working between two XP machines, but as soon as I try Remote Desktop I can't even get to the login screen without an error which gives a list of possibilities and concludes with "See your network administrator", which isn't very helpful.
I have ramped up the security level on Remote Desktop including turning on encryption etc. Could this be the problem? I will only get a few hours on the machine at a time so I need to be well-prepared before I attack this problem again. Any ideas?
EDIT: The error message is as follows, and this occurs before any login screen appears: