Legacy Software Issues
|
Current Status of Legacy Software: May 14, 2004 The HEC-6, Version 4.2 program has been recompiled and is availble from the HEC-6 download web page. April 30, 2004 The HEC-5, Version 8.0 program has been recompiled and is availble from the HEC-5 download web page. Problems Running HEC Legacy Software on Windows XP and Windows 2000 April 21, 2004
THE ISSUE: Certain HEC legacy DOS applications that ran successfully under Windows 2000 no longer function after installation of security patch KB835732. This came as a surprise to us, as it has to our user community. (Note: We have been aware for some time that these same legacy applications do not work under Windows XP and had planned on gradually resolving the issue). The solution to this issue will require that we at HEC re-compile these programs with a new compiler that’s compatible with the Windows XP and the newly patched Windows 2000 Virtual DOS Machine (VDM) subsystem. Unfortunately, this solution will not be possible for all of the affected legacy applications, as explained below. PROBLEM: The problem stems from the fact that some of our legacy DOS software programs were compiled with a compiler known as "The Lahey Extended Memory Compiler". At that time, this compiler allowed versions of our software to run in a DOS window and use what was called extended memory. This allowed these software products to use more than the DOS limit of 640K of memory and thus permit larger array dimensions that enabled larger-scoped applications to be successfully accomplished. Windows XP and Windows 2000 do not support a true DOS operating environment, instead emulating the basic functionality to enable running old DOS programs. The emulation does not extend to DOS memory management – a source of security concern. The security patch in question modified the emulated DOS memory management which has resulted in several of our legacy DOS software packages to no longer function. PROGRAMS THAT NO LONGER WORK: The following is a list of our frequently used legacy DOS programs that will not run on Windows XP or Windows 2000 (with the KB835732 security patch loaded):
PROGRAMS THAT STILL WORK: The following is a list of our frequently used legacy DOS software packages that will work under Windows XP and Windows 2000 (with the KB835732 security patch loaded):
PROBLEM SOLUTIONS: The following is a list of possible solutions to this problem, as well as what we plan to do about the problem for future work:
The only solution is to run HEC-IFH on a machine with Windows 2000 (without KB835732 security patch loaded), or an older machine with 98, ME, and 95. If you are in a USACE network environment, security will require that you be disconnected from the network until the patch is installed. The plan all along has been to incorporate HEC-IFH capability into HEC-HMS. Unfortunately, with the steady reduction in CW R&D funding available for such work, this has not been possible, and is not likely for at least another year. In lieu of using an older OS computer, a possible work around is possible using HEC-HMS to perform the runoff calculations for the interior area and HEC-RAS unsteady flow routing to route the flows through the pond. HEC-RAS has pumping capability as well as gravity outlets with flap gates. Analysis can be either single events or period of record analysis. However, you will have to perform the stage frequency analysis of the interior area separately in a statistical software package, such as HEC-STATS. Awkward but doable we know, but since we can neither control Microsoft's security patch approaches nor the ever increasing security demands for software, this will have to do for now.
Thank you for your patience in this matter. We are addressing these problems as they arise, and are attempting to provide solutions as rapidly as is practical. |