8. Trouble Shooting
Problem: Can’t talk to the modem.
Things to check: Make sure the modem cable is connected to the
port selected in the Modem Preferences. If the SD light on the
modem (Send Data) does not blink when you type in ZTerm, you probably
have a cable problem. Try typing ATH then hit Return; if the
modem responds with OK on the next line, then you are talking to the
modem.
Problem: You get the message “NO DIAL TONE” when trying to dial.
Possible causes: The modem is not connected to a phone
line. Someone else is using the phone. Your dial tone
doesn’t sound like what your modem is expecting. Try ATX0 (that’s
a zero) to tell the modem to not check for a dial tone.
Problem: During an XModem or YModem transfer, it keeps getting
errors after 2176 or 17408 bytes.
Possible cause: something in the data path (like a terminal server) is
not passing on the XON or XOFF character. For X/YModem, all
characters must be passed through. See if the terminal server has
a binary mode.
Problem: During a ZModem transfer, lots of errors occur after the
first few blocks.
Possible cause: a flow control problem with one of the
machines. Try setting a window limit to see if that helps.
If you are sending, go to the ZModem Options and put 2048 in for the
Window Limit. If you are receiving from a Unix system (using sz),
try the command “sz -w 2048 <filename>”.
Problem: Modem hangs up during a download or when receiving lots of
text.
Fix: If you are using hardware handshaking, you need to configure your
modem to ignore the DTR line. On most modems, the command is
AT&D0 (that's a zero).
MNP connect problems - try AT&Q0 to disable compression and error
control
Problem: When connected to a PC based BBS, a box is made up of
regular characters instead of line drawing characters.
Fix:
Make sure PC-ANSI emulation is selected and make sure the Strip Hi Bits
option is not checked.