Explorer

This program has performed an illegal operation and will shut down
EXPLORER caused an invalid page fault in
module PDM.DLL at 0167:4a01259d.
Registers:
EAX=00000000 CS=0167 EIP=4a01259d EFLGS=00010246
EBX=006ccb64 SS=016f ESP=0206fe44 EBP=00000000
ECX=006c8b60 DS=016f ESI=006ccd60 FS=124f
EDX=00000004 ES=016f EDI=006ccb54 GS=0000
Bytes at CS:EIP:
8b 10 ff 52 08 83 c6 04 eb c9 53 ff 15 f4 00 02
Stack dump:
00000000 006ccd40 006ccb48 00000001 4a01275a 006ccb44 006ccd40 00000000 4a012fed 006ccb48 4a012b06 006ca540 00000000 00000000 00000000 006c1060

Does anyone know what are the causes for these Stack dumps… It happens when there is a lot of activity on Line and sometimes on line it comes-up with WAOL causes an illegal ….same as above..
Thanks!!! And much appreciated…