Unable to connect to network printer

1 network hardwired, 2 PCs with Vista, and 1 network printer. I switched internet service and had to get a new modem and a cable router w/ 4-port switch. Each computer is on the same network, however the pc not connected to the printer is unable to print. Both pcs are able to connect with the internet. When I try to connect to the other pc through network it tells me that windows cannot access \\FRONTROOM-PC. Prior to switching the pcs where connected and both able to print. The Frontroom pc recognizes the back pc, however; the back pc pings the frontroom pc and gets no response back. Unsure what to do. Any help or suggestions is greatly appreciated!

 

Ok I fixed it, and for anyone else that might be having this issue check firewall settings in antivirus programs, it was the antivirus firewall that was not allowing communication. Simple thing to fix!