If when checking to see if your modem is properly installed and communicating with Windows XP, Device Manager says you have a resource conflict, try changing a modem's COM port. This changes the IRQ setting and eliminates a resource conflict with another device.
Open your modem's Properties screen by double-clicking its listing in Device Manager, or go to Start | Control Panel | Printers And Other Hardware | Phone And Modem Options, select the Modem tab, and double-click your modem (Figure 1).
Figure 1: Open your modem's Properties screen.
Open the Advanced tab and click the Advanced Port Settings button (Figure 2).
Figure 2: Click the Advanced Port Settings button.
If this option is not displayed, the modem doesn't support changing the COM setting. The only way to change the COM setting is to uninstall and reinstall your modem in Windows XP.
Select a new COM port from the COM Port Number pull-down menu (Figure 3) and click OK.
Figure 3: Pick a new COM port from the pull-down menu.
