Data Terminal Ready (DTR) Line Set to HIGH After Starting Windows Me (285894)


The information in this article applies to:

  • Microsoft Windows Millennium Edition
This article was previously published under Q285894
If this article does not describe your hardware-related issue, please see the following Microsoft Web site to view more articles about hardware:

http://support.microsoft.com/default.aspx/w98?sid=460

SYMPTOMS

After you start Windows Millennium Edition (Me), the Data Terminal Ready (DTR) line on serial communication (COM) ports is set to a HIGH state. You can observe this behavior with any modem that has control lights to indicate the state of different signals.

Disabling power management on the COM port does not change this behavior.

CAUSE

This behavior is caused by a design change in Windows Me.

RESOLUTION

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix should have the following file attributes or later: 
   Date       Time     Version     Size     File name  
   ----------------------------------------------------
   01/17/01   9:09pm   4.90.3001   13,047   Serenum.vxd

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

This problem may affect some third-party communications software that monitors the status of the DTR line, and cause such software to incorrectly detect the status of the modem or COM port. This problem might affect only modems that conform to European (CCITTV) specifications. Modems that conform to United States (IEEE) specifications may not monitor the status of the DTR line and may not be affected by this behavior.

For additional information about Windows Me hotfixes, click the article number below to view the article in the Microsoft Knowledge Base:

295413 General Information About Windows Millennium Edition Hotfixes

Modification Type:MajorLast Reviewed:8/8/2006
Keywords:kbHotfixServer kbQFE kbfix kbprb kbQFE KB285894
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