Selective TCP/IP question

I have two sworkstations on my network that are unable to ping SERVER2, nor can SERVER2 ping those systems. Every system is on the same subnet and all systems can ping each other fine with the exception of these two workstations not able to ping just the SERVER2. The workstations get handed their info via DHCP from another server like all the rest of the workstations and I have plenty of leases available. Any ideas….