Invalid page fault opening control panel

One of my end users has a Dell laptop running Win98 SE. When he tries to open the control panel, he gets a pop up message saying "Explorer has performed an illegal operation, invalid page fault in module Kernel 32.dll@0177:bff711be." The computer freezes up and he has to use the power button to reboot the machine. I ran Scandisk: Defrag: Sys file checker: Registry first aid: all to no avail. I booted to safe mode and tried to open control panel with the same results. I did a complete Win98 reinstall but that didn't help either. Other that formatting the hard drive and starting fron scratch, I don't know what else to try. I know many of you experts out there know exactly what's causing this and how to fix it.