Microsoft KB Archive/886386

= COM ports are not created when you install a modem in Windows XP Service Pack 2 =

Article ID: 886386

Article Last Modified on 11/19/2004

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APPLIES TO


 * Microsoft Windows XP Professional
 * Microsoft Windows XP Home Edition

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SYMPTOMS
When you install an internal, controller-based modem on your Microsoft Windows XP Service Pack 2-based computer, the required COM ports do not appear in Device Manager.

You may also see an event error in the System log. This error reports Serial.sys as the source of an event ID 7.



CAUSE
This problem may occur if you install an internal, controller-based modem on a computer with 10 or more data buses.



WORKAROUND
To work around this issue, install the modem on bus 0 or on bus 1. For more information about how to do this, contact the manufacturer of your computer.



STATUS
Microsoft has confirmed that this is a bug in the Microsoft products that are listed in the &quot;Applies to&quot; section.



MORE INFORMATION
Controller-based modems are modems that do not require any CPU power from the host computer.

You may be able to determine the number of bus paths that are installed on your computer by viewing the BIOS information. For more information about how to do this, contact the manufacturer of your computer.

Keywords: kbtshoot kbhardware kbcommport kbprb KB886386

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