Explorer.exe crashing when opening movie files

hi there

since yesterday night i noticed a bizarre crash on my win 7 32-bit machine when i open .mkv or .wmv hi res video files.... although the video opens, explorer crashes, either when i do right click > open > windows media player classic or if i open it with windows movie player..

anyone? solutions or fixes? i have 2 graphic cards on my netbook so i tested with the nvidia and with the onboard intel video card but same thing happens, so it's not a video card drivers problem and i didn't install anything new recently...

thanks
gabrio

from event viewer:

Faulting application name: Explorer.EXE, version: 6.1.7601.17567, time stamp: 0x4d6727a7
Faulting module name: kernel32.dll, version: 6.1.7601.17617, time stamp: 0x4dce1ef5
Exception code: 0xc0000005
Fault offset: 0x00047dd4
Faulting process id: 0xc60
Faulting application start time: 0x01cc45e3a8b638c8
Faulting application path: C:\Windows\Explorer.EXE
Faulting module path: C:\Windows\system32\kernel32.dll
Report Id: 24b0ed2e-b1d7-11e0-b6e2-00235474e170

SOLVED : before going to screw up more things, by the way, nice thread here Troubleshooting Explorer.exe Crashing Issues from our forum... i realized that the problem with the movies may be codecs-related so i thought i would give it a shot so i removed K-Lite codecs pack (with MPC) that i had installed. cleaned registry properly (cc cleaner + registry mechanic), restarted, reinstalled K-Lite Codecs pack fresh from their website and voilà works like a charm and no more Explorer.exe crash..

however...the "usual" misteries... why did it start crashing in first place? i don't know. but nevertheless it works now ;-)