Generally, there will probably always be an occasional disconnect. After all, we are dealing with phone lines being pushed to their limits with V.34 and V.90 modems. Phone lines were designed for voice, not for data transmission. But if you're getting a lot more than the occasional disconnect, something is wrong and you should methodically follow the steps below.

Reason & Solution #1:

Disconnections may be caused by momentary drops of DTR (Data Terminal Ready). By default, most modems respond to a drop of DTR by hanging up. With US Robotics modems add S25=200 to your Modem String, with other modems add S10=50. This sets the duration, in hundredths of a second, that DTR must be dropped so that the modem doesn't interpret a random glitch as a DTR loss.

Reason & Solution #2:

A similar possibility to the one above is that your modem could not distinguish between a line hit, or other disturbances that momentarily break the connection, from a true disconnect by the remote modem. Add S10=100 to the Modem String to set the duration, in tenths of a second, that the modem waits after loss of carrier before hanging up.

Reason & Solution #3:

If you have call waiting and a call comes in while you are connected to Ontarioeast.net, your modem might interpret the second signal as a disconnect by the remote modem. Ask your phone company how to temporarily disable call waiting. Also, keep in mind that Ontarioeast.net has an idle timeout. If there is no modem activity on your end for 20 minutes, you will be disconnected.

Reason & Solution #4:

If you suspect line noise, try solutions #1 and #2 above. Also, listen in on the line for static, ask your phone company to test the line (although they usually only test for voice grade as opposed to data grade), and try reducing your baud rate (a.k.a. port speed). Also disconnect EVERYTHING from your phone lines, including a laser printer from the electrical outlet.

Do not use devices that allow you to connect your phone line to an electrical outlet. Also, keep the phone line at least three inches away from electrical cords, extension cords, printer cables, etc. Inductance from electrical lines and radio transmitters wreaks havoc with phone lines. And avoid using phone splitters of any kind.

Reason & Solution #5:

One common cause of disconnects is modem incompatibility between your modem and the remote modem. No modem is completely compatible with every other modem. Be sure to check with the modem manufacturer periodically for firmware and driver upgrades. Do not assume that just because your modem is new that it contains the latest firmware and drivers.

Reason & Solution #6:

Check your phone cable for defects. Or better yet, just replace it with a brand new one. Also, if you have an external modem, make sure your modem cable connections are tight and the cable is also free of defects. Generally, the modem cable should be replaced every year or so, depending of course on frequency of use.