KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q71634: Loading 10net Redirector High Hangs Unisys Workstation

Article: Q71634
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:5.0
Operating System(s): 
Keyword(s): 
Last Modified: 22-NOV-1999

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

- Microsoft MS-DOS operating system version 5.0 
-------------------------------------------------------------------------------

SUMMARY
=======

Loading one part of the 10net redirector (10NET.EXE) high into the upper memory
blocks (UMBs) causes the Unisys 386 workstation to hang. A cold boot is required
to restart the workstation.

This is NOT a problem with MS-DOS version 5.0; this is a problem with the DCA
10net software. There are two problems with the 10NET.EXE file:

1. 10NET.EXE moves its code to 64K above the current code segment without
  checking the top of memory value in the program segment prefix. If it is
  loaded into a UMB, results may be unpredictable.

2. 10NET.EXE's header has a nonzero initial system stack (SS) value and a zero
  initial stack pointer (SP) value. When DOS pushes the return address on the
  user stack to transfer control, it actually goes into the 64K region above
  the SS. This mode of control transfer may lead to unpredictable results. In
  the case of loading into UMBs, it could be pointing to ROM or an unmapped
  region.

Additional query words: 5.00 noupd

======================================================================
Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS500
Version           : MS-DOS:5.0

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

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.