Black Box MD1641A Manuale Utente

Try entering the 

(List Online Diagnostics) command in on-line

mode, making a screen print of the diagnostics listing, and
checking for parameters that may be unacceptable (number of re-
trains, round trip delay, etc.). 

Your computer and the remote computer may be set to different
word lengths, stop bits, or parities. If you have connected at 8-N-1,
try changing to 7-E-1, or vice-versa, using your communications
software.

You may be experiencing line noise. Enable error correction, if it is
disabled, or hang up and call again; you may get a better connec-
tion.

At speeds above 2400 bps, the remote modem might not use the
same transmission or error correction standards as your modem.
Try connecting at a slower speed or disabling error correction.
(With no error correction, however, line noise can cause garbage
characters.)

Try entering the 

(List Online Diagnostics) command in on-line

mode, making a screen print of the diagnostics listing, and
checking for parameters that may be unacceptable (number of re-
trains, round trip delay, etc.). 

Communications devices can be accessed by only one application at a
time. Under DOS or Windows 3.1x, you can run either your fax software
or your datacomm software, but not both at the same time, unless you
have a special communications device management application. In
Windows 95, you can have data and fax communication applications
open at the same time, but they cannot use the same modem at the
same time.