remote network connectivity problem

Got two Cisco routers to connect my workplace and the network implemented with a remote workspace trough a dedicated line. The problem is I can ping the other router and the machine attached to it but can’t get it to show up on windows network neighbourhood. Had to assign a different ip number in the 3rd octet to get ping responses and traces to the router and the machine, also have both routers as gateways on TCP/IP properties being the local one set up by default. Do I have to expand the subnet mask to the next class?