Modem wont talk to ISP

Hi, trying to help a friend get his modem to work with his ISP. He has a newer gateway running XP Media. When dialing his local ISP the modem will not connect. Brought it to me, as if I know the answers. I verified that I too could not connect to his ISP with his machine but I could however connect to my ISP with no problems. I swapped his internal modem with a know working USR model but still have the same problem. The error that pops up from the system is code 678 - remote computer did not respond. I finially hooked up an external modem to the com1 serial port and still the same problem. Actually, other than hearing the dialing sounds, there are no sounds that indicate the computer modem and ISP modem are trying to connect. This is not the case when I dial my ISP using his machine and any modem. I have followed suggestion from Microsoft concerning the 678 error but that has not helped at all. Might his ISP, a small local ISP that is part of the educational MICHNET system, not be compatable with XP Media Center? Thanks

Are you dealing with Dial-up or PPOE DSL? Often not the correct telephone access number, incorrect userID/password, proxy setting, or TCP/IP settings. to fix TCP/IP settings, completely uninstall the TCP/IP (in Control Panel - Network) Reinstall from the Modem installation CD Get tech-support at the ISP to assist walking throught the "create new connection". In the meantime, you could use the command line procedures if you are familiar with them, If not wait and follow instructions from the ISP tech support. You know it is a good system, since it connects via your ISP. Frustrating and annoying. It's not just the small ISP's, but even major dial-ups too. Best Regards

Thanks Dough, Yes, the problem is with dial-up not DSL. As I can not connect to the small ISP dialup but can to Earthlink's dialup on this computer, wouldn't that eliminate the TCP/IP problems? I have contacted the ISP for help but so far no answer from them. Thanks again for your help.