Problem:

Stress Isometric does not create a drawing file, why? Reason #4.

Solution: 

Program launching a 2nd executable

Program could potentially be launching a separate executable to convert the *.L00 files to isometric drawing. Answer the following questions:

1. Check in the model directory, is a "modelname.PCF" file generated?
2. Check in the model directory, is a "modelname.apiso" file generated?

If answered YES  to both questions and still no Isometric drawing was created, then most likely cause would be that the Operating System is blocking AutoPIPE to launch that separate *.EXE process "ExecISO.exe" from installation directory.

One other suggestion, confirm Iso Viewer selected under Isometric Manager Settings. Try again. 

Is a Stress Isometric created, 

If No, go to next reason below.

See Also

OPIM Stress Isometric Troubleshooting Guide

Stress Isometric does not create a drawing file, why? 

Reason #1: Test using an AutoPIPE example model

Reason #2: Model's filename length is too long 

Reason #3: Possible different filename and/or location

Reason #5: Prevent access to registry editing tools

Bentley AutoPIPE