After Remote Desktop logs on, it logs off immediately, why?

Hi,

Got this working yesterday.
PC2 opened Remote Desktop on PC1 and allowed me to work on PC1 remotely.

Today, when PC2 connects to PC1, rightafter the log on message appears a log
off message.
Without any error of failure messages. Checked settings and rebooted both
pc's but at no avail.
No intermediate updates.

Configuration
Gateway IP 192.168.2.10
PC1 fixed IP 192.168.2.11, SP1a, no firewalls, NAV2003 AutoProtect on.
PC2 fixed IP 192.168.2.12, SP2, firewall off.
Identical user accounts of both machines.
Remote Users added to Remote User group (IUSR_PC? or similar).


Any suggestions ?


TIA,
John7