TCP/IP

Authentication could not be sent to 152.158.100.68. there may be a problem/conflict with the TCP/IP protocol.

Trying to connect through the AT&T network dialer but get the above error message. have tried a few things to no avail. Just cannot get the dialer to connect. Any ideas would be appreciated. I know the topic has nothing (well almost) to do with the question but no other topic to choose from