HP Compaq Presario,Presario 2100 Reference Manual page 80

Troubleshooting and Maintenance
Troubleshooting Your Notebook
If the modem doesn't dial or no dial tone is detected
Check all cables and connections.
Connect a standard telephone to the phone line and make sure the line is working.
Make sure someone else isn't using the same phone line.
Try another telephone line, preferably one normally used for a fax machine or
modem.
If you're in a foreign country, the dial tone may not be recognized by the modem.
In Control Panel, open Phone and Modem Options. Try disabling the option that
waits for a dial tone.
If the modem dials incorrectly
Check the telephone number you entered, including any digits required for
outside access or long distance.
In Control Panel, open Phone and Modem Options. Check the dialing options—
look for duplicate digits for outside access or long distance.
Make sure the number you're calling isn't busy.
If you're in a foreign country, the dial tone may not be recognized by the modem.
In Control Panel, open Phone and Modem Options. Try disabling the option that
waits for a dial tone.
If you have call-waiting, disable it—your telephone company can provide
instructions.
If the modem dials but doesn't connect
Make sure you're using an analog telephone line (2, 3, or 4 wires). You must
not use a digital line. In a hotel, ask for a data line.
Try another telephone line, preferably one normally used for a fax machine
or modem.
The modem at the other end may have a problem. Try dialing to a different
modem.
If the modem isn't detected
Check the modem setup. In Control Panel, open Phone and Modem Options.
Check the COM port.
74 Reference Guide