why does com port 1 keep taking over for modem after reboot?

Question

just formatted and the modem defaults to com port 1 and won't work. have to manually change ports. will stay on com port 3 until reboot.

Answer 1

The COM port that a modem is connected to also has an IRQ assigned to it. If modems are assigned to the same IRQs as other devices, they must use an alternate IRQ. Fortunately, many of today's modems are capable of addressing alternate IRQs. It is very important when assigning IRQs to make sure no two devices will need the same IRQ at the same time.

Check your device manager and make sure you don't have conflicts. control pad-system-hardware-device manager

Answer 2

Hi,

You apparently have a software modem that is plug and pray and it is conflciting with your onboard comm ports.

Reason:
You BIOS detects your onboard comm ports and assigns an IRQ to them (comm1 & comm3 both use IRQ2 and comm2 & comm4 both use IRQ3. These are standard assignments unless you choose auto assign and then there is still the possibility of a conflict with another device.). After assigning IRQs to your onboard comm ports, your system then tries to assign one to the software modem as the driver gets loaded. Since you probably have a plug and pray modem, it does not play well with others and thus assigns a standard IRQ to the modem.

As the individual who suggested disabling the onboard comm ports, disabling the onboard comm ports will stop the modem from having a problem.

George

Answer 3

Let it have it then.

Enter your bios and disable onboard com ports or set the onboard to 3.

COM 3 03E8

Answer 4

check in your bios, and see if there is a setting for the modem, and change it to the com you want it to be on, it defaults to com 1 if there is a bios setting

Answer 5

I think when windows boots it reassigns devices with whatever com is available. Have you tried updating your drivers?