KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q89917: Copying to LPT Port in MS-DOS Session Slow

Article: Q89917
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:3.1,3.11
Operating System(s): 
Keyword(s): 
Last Modified: 09-OCT-1999

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Windows versions 3.1, 3.11 
-------------------------------------------------------------------------------

SYMPTOMS
========

When you use the MS-DOS level COPY command to copy a file to an LPT port in a
Windows 3.1 MS-DOS session, Windows appears to be completely frozen until the
MS-DOS command has finished executing.

This delay only occurs in 386 enhanced mode. The error does not occur in Windows
3.0 or 3.1 running in standard mode.

WORKAROUND
==========

To work around this problem, you can either

- Edit the SYSTEM.INI file, and add the following lines to the [386enh]
  section:

        ReflectDOSInt2A=ON
        TimerCriticalSection=0

  NOTE: If you are using a network that requires TimerCriticalSection= set to a
  higher value, then setting this to zero may adversely affect the running of
  MS-DOS applications.

  -or-

- Run Windows in standard mode.

MORE INFORMATION
================

Below are the definitions for the two SYSTEM.INI switches listed above. These
definitions come from the SYSINI.WRI file that comes with the Microsoft Windows
Resource Kit for operating system version 3.1.

ReflectDosInt2A=<Boolean>

Default: False

Purpose: Indicates whether Windows should consume or reflect DOS INT
2A signals. The default means Windows will consume these signals and
therefore run more efficiently. Enable this setting if you are running
memory-resident software that relies on detecting INT2A messages.

TimerCriticalSection=<milliseconds>

Default: 0

Purpose: Instructs Windows to go into a critical section around all
timer interrupt code and specifies a timeout period (in milliseconds).
Specifying a positive value causes only one virtual machine at a time
to receive timer interrupts. Some networks and other global memory
resident software may fail unless this setting is used. However, using
this setting slows down performance and can make the system seem to
stop for short periods of time.


Additional query words: box 3.10 3.11 2a

======================================================================
Keywords          :  
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin310 kbWin311
Version           : WINDOWS:3.1,3.11

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.