NewInstance

Got the problem this evening, and I’ve been getting crazy for a couple of hours.

Quick solution for the inpatients: the “fast user switching” and the “welcome screen” feature in XP makes Remote Desktop not work properly. So, disable it and you’ll solve 90% of rdesktop problems. (Notice that those two options needs to be enabled in order to make the Seamless RDP work)

What happens is that the “fast user switching” misfeature drops connections on logout (and don’t starts connections on startup until some user logs in). If there is no user logged in or if the user logs out, the networks gets disabled, and you cannot connect using Remote Desktop.
When you try to open a remote desktop and the same user is already logged in locally, the local user gets disconnected and computer display the “fast user switching” screen, but doing that also drops all the connections, and from the remote desktop client you get a black screen (just after inserting the user name and password).

How to solve:

1. Disable the “fast user switching” and the “welcome screen”
Open User Accounts in Control Panel.
Click Change the way users log on or off.
Clear the “Use Fast User Switching” check box.
Clear the “Welcome Screen” checkbox.
Apply the changes.

2. If you still get disconnections on user logout, try setting up the KeepRasConnections key on the registry:
Open regedit and go to the path:
HKLM\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
Create a new String value, or modify the existing value, called “KeepRasConnections” and set it to “1″.
Exit your registry and restart Windows, as usual

This should work. It did, for me.