FC modem to a v. Inactivity can also cause disconnections. Net has a 25 minute inactivity time-out, meaning that if you do not send any data over your Internet connection for 25 minute, your account will be disconnected. Most Internet dialer software will automatically drop the network connection after a few minutes of inactivity. Minimize the window, and your connection will hold up.
Some modems are better than others at holding connections.
If that is not the case, consult your modem's manual for details. External modems rely on a serial chip inside your computer for the transmission of information across the serial interface between the computer and modem. Unfortunately, older computers may have a serial chip that simply can't keep up with a 28.8 modem. The 16550 chip, on the other hand, is reliable up to 115200. You can check to see if you have an older 8250 or 16450 serial chip in the MSD program.