Compaq Armada V300 Series Reference Manual page 86

Set the modem to ignore dial tones—If the modem receives
a dial tone it does not recognize, it will not dial and will
display a No Dial Tone error message. To set the modem to
ignore all dial tones before dialing:
1. Select StartÆSettingsÆControl PanelÆModems.
2. Select your modem, then select PropertiesÆConnections
tab, then clear the Wait for Dial Tone Before Dialing check
box.
If you continue to receive the No Dial Tone error
message after clearing the checkbox, click StartÆSettingsÆ
Control PanelÆDialing PropertiesÆselect USA in the "I am
in:" drop-down box, then again clear the Wait for Dial Tone
Before Dialing check box.