How to fix "GTA IV FATAL ERROR: SMPA60" in GTA IV for PC

GTA IV for PC is crashing and the error message says "GTA IV FATAL ERROR: Unrecoverable fault - Please restart the game." The title of the error dialogue box is "GTA IV FATAL ERROR: SMPA60." How can you fix this? Answer: This error may occur if you have installed mods, especially ones that affect cars. Removing the modded cars has fixed this issue in many cases.