Hi, I’m having a strange problem communicating with some hosts on my network. I have two networks 192.168.10.x and 192.168.13.x and network traffic is routed via Cisco 801 routers over ISDN. The problem is that I can’t access a host on one of the networks from the other until the computer I am accessing pings the computer trying to access it, for example: Host-A cant access Host-B until Host-B pings Host-A. This problem only occurs across the two networks. Any ideas to where the problem may be would be appreciated. For more information: The networks are on a domain and run DNS and DHCP. All workstations are XP and servers are 2003 Standard. Thanks!