Question : Windows Remote Desktop, suddenly a black screen - no login

I have two computers at office, one XP, one Windows Server  2003 R2.
I access both of them remotely, using Remote Desktop.
I do not use a VPN, I have just had the router assign different ports.

The server is always there, haven't had any problems, I can always connect.

Now, to the problem:
The XP machine is unreliable. After several successful connections, I suddenly get a black screen (it is obvious that it connects since I see the white panel slide down from the top of my screen).
But - I only get this black screen - no login box.
After this, there seems to be no way out, I have to go to the office, log in directly, when back home again I can connect to it again, until it suddenly finds out it is about time to show this black screen.

It is crucial to get this fixed, I am totally dependent of accessing the machine remotely.
Any clues? Is there a way to tune the XP machine? A limit that needs adjustment or something? Does it think too many are connected, while actually no one at the moment is connected?

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Ingvar

Answer : Windows Remote Desktop, suddenly a black screen - no login

look for ACPI on BIOS