Merci pour cette réponse rapide

et super tuto !!!
Bizarrement, depuis que j ai poster ici, l explorateur n a pas replanté...j ai réussi a installer kapersky, mais ca rame grave, quelque chose ralenti la machine !!!
J ai fait les 2 tests, voici les résultats...:
---------------------------
WhoCrashed
---------------------------
External exception C0000006.
---------------------------
OK
---------------------------
en gros je peut pas copier coller, mais c est marqué qu il n y a rien !!!
et
aswMBR version 0.9.5.256 Copyright(c) 2011 AVAST Software
Run date: 2011-05-17 20:37:00
-----------------------------
20:37:00.718 OS Version: Windows 6.1.7601 Service Pack 1
20:37:00.718 Number of processors: 2 586 0x170A
20:37:00.718 ComputerName: JC-PC UserName: JC
20:37:03.697 Initialize success
20:37:17.628 Disk 0 (boot) \Device\Harddisk0\DR0 -> \Device\Ide\IdeDeviceP1T0L0-1
20:37:17.644 Disk 0 Vendor: WDC_WD5000BEVT-22ZAT0 01.01A01 Size: 476940MB BusType: 3
20:37:19.687 Disk 0 MBR read successfully
20:37:19.687 Disk 0 MBR scan
20:37:19.687 Disk 0 Windows 7 default MBR code
20:37:21.700 Disk 0 scanning sectors +976771120
20:37:21.715 Disk 0 scanning C:\Windows\system32\drivers
20:37:24.461 Service scanning
20:37:25.990 Disk 0 trace - called modules:
20:37:26.021 ntkrnlpa.exe CLASSPNP.SYS disk.sys ACPI.sys halmacpi.dll ataport.SYS pciide.sys PCIIDEX.SYS atapi.sys
20:37:26.021 1 nt!IofCallDriver -> \Device\Harddisk0\DR0[0x85d61410]
20:37:26.037 3 CLASSPNP.SYS[8ac0459e] -> nt!IofCallDriver -> [0x858a9918]
20:37:26.037 5 ACPI.sys[8aac73d4] -> nt!IofCallDriver -> \Device\Ide\IdeDeviceP1T0L0-1[0x858e5030]
20:37:26.037 Scan finished successfully
20:37:37.144 Disk 0 MBR has been saved successfully to "C:\Users\JC\Desktop\MBR.dat"
20:37:37.144 The log file has been saved successfully to "C:\Users\JC\Desktop\aswMBR.txt"
Voila !!!