Yes you should be able to use the NIC for LAN
and the modem for dial-up.
I just mentioned HP as there is a known issue for some of the
Pavilion models after an upgrade to XP.
This is what I would try then.
I would boot to safe mode.
I would delete the current dial-up connection in
Control Panel | Network Connections.
Then uninstall the modem from Device Manager.
Reboot to normal mode and let the modem
redetect and re-install.
In Device Manager, go to the Modem properties | Diagnostic tab |
and click on "Query modem" and see if that succeeds.
(Check Modem Properties | Advanced tab | Advanced port settings button |
and see if you can change the Com port assignment if needed)
Another thing to consider would be to move the modem to a different
PCI slot.
When you create a new dial-up connection, it should have checked:
Client For Microsoft Networks
Quality of Service Packet Scheduler (optional)
Internet Protocol TCP/IP (obtain IP Address Automatically)
Advanced tab - ICF can be checked or unchecked -
depending on Fire Wall situation.
Make sure that the phone line connection to the modem is in good
working order.
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