HEC-RAS SNET analysis program fails to run (DOS Version only)

When attempting to run the HEC-RAS analysis engine, you may get an error message:

Fatal Error TNT 10118: Can't load EXE file: C:XXX tstyle.dll
Memory error: insufficient physical memory available

What is happening is that the HEC-RAS analysis engine cannot get enough physical memory space from DOS to load itself. The AutoCAD environment variable ACADMAXMEM needs to be set in the batch file used to launch AutoCAD (i.e., ACAD.BAT, ACAD12.BAT, or ACAD13.BAT) to reduce the amount of exteneded memory that AutoCAD takes for itself. By default, AutoCAD takes all extended memory.

The environment variable ACADMAXMEM specifies the maximum amount of memory in bytes that AutoCAD can request from the operating system. By reducing this number, it frees up memory for use by the HEC-RAS analysis engine.

A line needs to be added in the batch file:

SET ACADMAXMEM=XXXXXXXX

where XXXXXXXX is the amount of bytes that AutoCAD can request from the operating system for strictly its use. If this environment variable is not set, then AutoCAD will use all available extended computer memory. We suggest that you specify a number that is 2.5 mbytes (2,500,00 bytes) less than the maximum available extended computer memory. This will allow the HEC-RAS analysis engine to run.

For additional details, please refer to your AutoCAD Installation Guide and Reference Manual.