Issue:
When opening 3ds Max, an error message appears “Maximum Nested Error Dialog Depth Reached” along with a MAXScript window containing various MAXScripts/Macroscript tabs.
Maximum Nested Error Dialog Depth Reached
Attempt to display more than the maximum number of simultaneous error message dialogs occurred.
See the error log file for additional error messages.


Causes:
A corruption within the 3ds Max user files has triggered an issue with the 3ds Max load sequence.
Solution:
Reset 3ds Max using the steps in the article: Resetting 3ds Max / 3ds Max Design to default user settings.
See also:
- Send To Maya, Motionbuilder and Mudbox features are not working in 3ds Max 2019.3 and later versions.
- Scene objects become Bounding Boxes in 3ds Max Viewport