Disconnection Troubleshooting Guide
For the most part, sporadic and persistent disconnections can
be cleared up by adjusting configuration options, updating firmware
and drivers and weeding out other local factors. This guide explains
the most common causes and includes the most frequent solutions
to disconnection problems.
Editor's Note: Keep in mind that standard telephone lines were
designed for voice, not data transmissions. High speed (V.34 and
V.90) modem connections push the physical limitations of any voice-grade
line. Connection problems are sometimes (but not always) due to
conditions on the telephone network.
If data isn't sent or received for 20 minutes, our server assumes
you've left your computer and terminates the connection. No data
is transferred while you're composing E-Mail, so if it takes
you longer than 20 minutes to type a message, you may be disconnected.
To avoid this, simply "do something" (load a webpage,
check for new messages, etc) at least once every 20 minutes.
If another program tries to use the modem without checking to see
if it's already in use, you may be disconnected. Disable all
programs that may use your modem, such as fax or terminal software.
If you have call waiting and a call comes in while you're connected
to Michcom.net, the "call alert" beep may cause your
modem to disconnect from Michcom.net. To prevent this from happening,
disable call waiting. This can most commonly be accomplished
by inserting *70, before the number being dialed.
Sometimes, the FIFO buffer settings in Windows 95/98 will cause
connection problems. We've observed that "turning down" the
buffers frequently clears up disconnections. Find your modem
properties in the control panel (under "modems"), select
the connection tab, and click "port settings". Set
both buffers to the lowest possible setting.
Try setting your "maximum connect speed" to 57,600 instead
of 115,200. If that doesn't help, bring it down to 38,400 and see
if the disconnections go away. You'll find this setting under the
modem properties in the control panel.
By default, Win 95/98's TCP/IP drivers use DHCP for WINS resolution.
We suggest that you disable WINS resolution. Select TCP/IP under
network properties in the control panel and push the properties
button. Select the WINS configuration tab. Make sure "Disabled" is
Momentary Loss of DTR
Disconnections may be caused by momentary loss 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 Init String,
with other modems add S10=50. This sets the duration, in hundredths
of a second, that DTR must be dropped before disconnecting.
Momentary Loss of Carrier
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 Init String to set the duration,
in tenths of a second, that the modem waits after loss of carrier
before hanging up.
One common cause of disconnects is an incompatibility between your
modem and the remote modem. No modem is completely compatible
with every other manufacturer's equipment. Hardware manufacturers
frequently resolve this type of problem by releasing new firmware
and drivers. Be sure to check with your modem manufacturer periodically
for such upgrades. Do not assume that just because your modem
is new that it contains the latest firmware and drivers! It usually
Other Equipment on the Line
Sometimes other telephone equipment in the home can cause a modem
to disconnect, even if it's not plugged into the same phone jack.
Telephones, answering machines, fax machines, other computers,
and anything else that might be plugged into your phone line
could be introducing conditions onto the line that cause a disconnection.
Unplug everything except for your modem and see if the problem
If there's too much noise on your phone line, you may be unexpectedly
disconnected. If you suspect that this may be a problem, contact
the phone company and have them test the line for noise.
None of the Above
Okay, so you've tried everything we've suggested and you're still
Contact tech support and explain your situation. Include
as much detail as possible, including the type of modem, how
long the problem has existed, how frequently you're disconnected,
when you're most frequently disconnected, etc. We'll do our best