Tcp/ip Connectivity Problem On a Lan


How are you?

I have about 5 macs in a network of 30 that cannot access the web. All are dhcp, all can see server osx 10.4, all can get receive email which is a linux server. I can ping the adsl router, I can do a tracert to, the network settings info on all the screens is showing like the macs that do work yet no internet access? I managed to allocate a static ip to one that wasn't working and then changed is back to dhcp and this corrected the problem for this machine only, nothing I have tried on the others works.

Any ideas?

Muchos gracias