I have a Cisco 1841 WAN router that connects my company to a japanese network for a few users. Their pc's were configured from the mother company before they arrived here to use the 1841 IP as their primary gateway, my DC as DNS. I don't have a secondary DNS at this time. The problem is that every time I plug the 1841 into my switches after about 10-15 min the network drops all the other users. This router was already here when I inherited this position, and hasn't been an issue until a server that was the secondary DNS had a meltdown. I don't know Cisco very well, but had the WAN circuit provider checked the 1841 out and they didn't detect any malfunction. I'm suspecting that there are some DNS changes that need to be made to the DC to accomodate this device. Any help would be appreciated.