Windows 2K and Internet Email

We have a Small Business server network on a NT4 os platform and in the past have had all Win98 workstations. We implemented 2 new P4 1.2 Ghz workstations with Win2k. We use Outlook 2000 for our Intranet as well as internet communications. However the two new workstations refuse to see the pop3 or smtp mail services of my isp while with the same configuration the Win98 machines we have no problems. Any body have any thought on the matter? Or is there additional information needed?