TCP/IP Addressing Scheme

Recently, we have increased the number of ip addresses needed to over 240, so we decided to go to a class “B” network. We used the “172.23.16.0” with subnet mask of “255.255.240.0”. We used a different subnet for different locations. Location “A”172.23.16.1-254, location “B” 172.23.17.1-254, etc. The PDC is on 172.23.16 subnet, the problem is all the others have inconsistent problems seeing each other. I have setup a “WINS” and “DNS” server to try and eliminate problem, but I cannont seeany difference. Is there something wrong with my subnetting or something that I have missed?