Although quite long in the tooth now Gmax can still be used to mesh content for various games (
in particular Flight Simulator 2002 and Flight Simulator 2020), although a few
additional steps may necessary in between. With that said, for Windows 10 and Windows 11 there may be some compatibility issues to contend with that crash the application on startup. The likely cause of this is the Gmax using the wrong viewport driver to render content, that's the
HEIDI (software),
OpenGL and
Direct3D (hardware) selections typically accessed from
Customize » Preferences » Viewports - Display Drivers, which can't then be accessed and changed. When this happens a workaround can be used to add a 'flag' to the Gmax shortcut forcing the
gmax Display Setup dialogue to appear so the correct option can be set.
To set the flag, right-click the Gmax Desktop icon and select
Properties. In the
Shortcut tab, append "
-h" (note the space
before '-h') to the
Target: file path e.g.;
"D:\Program Files\gmax\gmax.exe"
Becomes
"D:\Program Files\gmax\gmax.exe" -h
Optionally, for Windows 10 and Windows 11 set the
Run this program as an Administrator checkbox in
Compatibility options.
Click
Apply then
OK to close, then restart Gmax. The
gmax Driver Setup dialogue will appear. Set an option; HEIDI, OpenGL or Direct3D (HEIDI is initially the safest to verify the application starts and no other issues are in affect). Once the application starts up correctly the driver can be changed if needed in
Customize » Preferences » Viewports - Display Drivers and the shortcut flag removed.
IMPORANT: the likely cause of the issue is the version of OpenGL Gmax uses to drive the viewports, which is obsolete or incompatible with the latest versions of the API. This is especially so for AMD powered graphics systems - setting OpenGL as the driver typically won't work so the driver should be Direct3D (hardware) or HEIDI (software).
Setting the Desktop shortcut flag to force gmax to start in 'safe mode'.
With the Desktop shortcut flag set the gmax Driver Setup dialogue appears with three options; HEIDI, OpenGL and Direct3D - HEIDI is the safest.
Gmax open and running on Windows 10 once driver is correctly set