SYMPTOMS
Assume the following scenario. In Microsoft Windows XP, you
run a 16-bit application for which the following conditions are true:
- The application is running in a Windows NT Virtual DOS Machine (NTVDM)
environment.
- The application accesses a COM port on the computer.
In
this scenario, you notice that another 16-bit or
32-bit application cannot access the same COM port until you quit the first
16-bit application.
RESOLUTION
Hotfix information
A supported hotfix is now available
from Microsoft, but it is only intended to correct the problem that is
described in this article. Only apply it to systems that are experiencing this
specific problem. This hotfix may receive additional testing. Therefore, if you
are not severely affected by this problem, we recommend that you wait for the
next Windows XP service pack that contains this hotfix.
To resolve
this problem immediately, 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:
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.
Prerequisites
You must have Windows XP Service Pack 1 (SP1) or Windows XP
Service Pack 2 (SP2) installed before you apply this hotfix.
Restart requirement
You do not have to restart the computer after you apply this
hotfix.
Hotfix replacement information
This hotfix does not replace any other hotfixes.
File Information
The English version of this hotfix has the file
attributes (or later file attributes) that are listed in the following table.
The dates and times for these files are listed in Coordinated Universal Time
(UTC). When you view the file information, it is converted to local time. To
find the difference between UTC and local time, use the
Time
Zone tab in the Date and Time tool in Control
Panel.
Windows XP Service Pack 1
Date Time Version Size File name
----------------------------------------------------------
01-Dec-2004 06:03 3.10.0.103 92,224 Krnl386.exe
01-Dec-2004 05:56 33,840 Ntio.sys
01-Dec-2004 05:56 34,560 Ntio404.sys
01-Dec-2004 05:56 35,648 Ntio411.sys
01-Dec-2004 05:56 35,424 Ntio412.sys
01-Dec-2004 05:56 34,560 Ntio804.sys
19-Jan-2005 03:37 5.1.2600.1620 396,800 Ntvdm.exe
04-Jun-2004 00:43 5.1.2600.1562 245,760 Wow32.dll
Windows XP Service Pack 2
Date Time Version Size File name
--------------------------------------------------------
19-Jan-2005 03:12 5.1.2600.2598 420,352 Ntvdm.exe