I just got this. I'm on Win 10, 3dsMax 2019.3, Corona 4.1.
It get the error when Corona Improved Color Picker is activated, and I try to change the layer color of a layer in the Layer Explorer, as soon as i click the swatch the error dialog shows up full of this message. No problem when I switch the picker back to default. I have a faint memory of reporting this bug once. Maybe it's fixed in Corona 5? Haven't had the chance to upgrade, though I desperately long for memory improvements in this nightmare of a file…