My modem quit working after I installed my mouse or trackball

If both your modem and your pointing device are using either the same COM port (serial port) or the same interrupt (IRQ), the following problems may occur when you try to dial or connect:

• The modem may not dial or connect.
• Your computer may stop responding.
• The pointer may freeze, either momentarily or until you restart your computer.

To correct the problem, check the following:

• Make sure that there are no other hardware devices using the same interrupt as the modem:
  • COM1 and COM3: IRQ4
  • COM2 and COM4: IRQ3

If there is another device, such as a mouse, trackball, digitizer tablet, scanner, fax card, network card, or sound card, using the same interrupt, do one of the following:

• Change the interrupt of the modem or the other device.
• Remove the other device from your computer system.

For information about how to change the interrupt of the modem or other device, see the manual for the device or contact the manufacturer. The method used to change the interrupt depends on the device because it may be a jumper, a DIP switch setting, or software.

• Check your modem configuration to make sure the IRQ setting on the modem matches the selected COM port.