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"port open" when changing modems

I replaced a modem on our fax computer. The modem I took out was on com port 3. The com port in the device manageer is com1I uninstaled the modem before removing the old modem, replaced with a new modem and added driver.when I try to run a diagnostic I get error "port already open".  When I removed the new modem and put the old one back I did not get that error message. How can I close the port on Com3 so the new modem can use it?
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You can't "close the port" per se. I'd suspect one of three causes. I'm assuming that it's a plug 'n play PCI modem.

An interrupt conflict -- change slots with modem
A driver problem -- remove and re-install driver
A faulty modem -- try a different modem


The modem was working in another computer.
The device manager does not show any interupts. Its in the same slot as the other modem was.
I've reinstalled the driver several times. I did not get the error message "port already open" when I put the older modem back in. I've tried changing the com port in the bios and that didn;t help. There is something that is opening port 3 and preventing my new modem from using it.

Did you change slots? If not, I strongly suggest you do so. Because it's in same slot as other modem doesn't matter. Changing slots should force an ESCD reset and IRQ reassignment.
I changed slots and its the same problem. The window's title is "OpenComm" and the message is "port already open". I returned the modem to the computer it originally came from and it works there. Changing slots may reset the IRQ assignment but there never was any IRQ conflicts. I removed the previous modem. I have not received anyother comments and they are putting preasure on me to close it out
so I'm doing so. Thanks for trying

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