How to set up Windows NT (4.0)

Due credit

This information comes from one of Idiom's customers: Peter Turnquist. Thank you Peter! From here on it's mostly his words.

Most of the configuration settings are available via Dial-Up Networking, More, Edit entry and modem properties. Idiom's usual information covers most parameters. Just fill in the obvious fields with the values supplied when you signed up for your account. NT users need the following advice in addition.
Under Server, choose "PPP . . ." as dial-up server type, enable "TCP/IP" and disable the other network protocols. Disable "software compression," and enable "PPP LCP extensions." Software compression probably would work if parties at both ends of a link run NT. Instead, an Idiom client should enable the modem's hardware compression.
Under Server, TCP/IP Settings, let the server assign your IP and name server addresses even if you know what they are. Enable "default gateway on remote computer." "IP header compression" works sometimes but it is safer to disable it at least until essential function is satisfactory.
Under Script, choose "None" both before and after dialing.
Under Security, choose "Accept any authentication including clear text."
Login user-name and password are not accessible on demand as the above parameters are. Rather, NT automatically presents a form for these if it wants the information on dialup. One must leave the "Domain" empty on this form, and enable "Save password." Use the PPP login form of user name. To force appearance of the form so one may change user name and password upon dialup, the prerequisite is Security, Unsave password.