COM ports are not created when you install a modem in Windows XP Service Pack 2 (886386)


The information in this article applies to:

  • Microsoft Windows XP Professional SP2
  • Microsoft Windows XP Home Edition SP2

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 "Applies to" 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.
Modification Type:MajorLast Reviewed:11/19/2004
Keywords:kbHardware kbCommPort kbtshoot kbprb KB886386 kbAudITPRO
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