Hi Jim,Give up on the dreaded 14120 error. There is no Unified Field Theory for the error, and we'll have to wait for a Q article or a service pack to see that one hit the road.
You should be able to change IP addresses for your publishing rules. I've tested web and server publishing rules with dial up connections that recieve different IP addresses each time they dial up. I have to change the IP address on the Inbound Web Requests Listener, and I have to change the IP address in all of the Server Publishing Rules. Then I restart the services (and hope the restart doesn't cause the connection to drop), and they all work fine.
You might try stopping all of the ISA Services, then disable and reenable the adapter, and then start the ISA Services and see if that helps.
Tom
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Tom Shinder
http://www.isaserver.org/shinder/
Get It Here