Apple Express Fax/Modem - Manual (Page 160)

Connecting to older modems
Certain computers may have older modems that do not support the speeds,
error control methods, or data compression types your modem is using. If you
try to connect to such a computer using your modem’s automatic settings, your
modem may disconnect in which case you’ll get a No Carrier message.
If you are using communications software:
1 Open your communications software.
2 Open the Connection Settings dialog box.
3 Choose None under Data Settings in the Data Features pop-up menu.
This forces the modem to connect in a mode acceptable to the remote modem
and at the highest speed it can support.
4 Match your Data Settings to those of the remote modem.
You can also change the Data Settings once you have connected to the remote
modem by simply reselecting Connection from the Settings menu.
If you are using AT commands (see Appendix B):
m Use the AT&Q command to force the modem into asynchronous mode.
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