I have 3 networked PC's in the same workgroup, all of which are running Windows 2000. 2 of them can ping each other, but can not ping the 3rd PC. The 3rd PC is able to ping the other 2, but can not be pinged by these first 2. When I have Netbeui installed, I am able to share files and print to the 3rd PC. When Netbeui is not present, I am unable to share files. In either case , I can not browse the other 2 PC's from this 3rd PC. It only sees itself as a member of the workgroup and does not see the other PC's in the workgroup. I have uninstalled and reinstalled tcp/ip. I am able to boot this same PC to Win 98 and these problems disappear. Obviously it is not a problem at the physical or datalink layer. It seems to be a problem with the way TCP/IP is configured with the W2K operating system. Any ideas as to what would cause this ?