help processus explorer.exe instable

Bonjour,
Mon processus explorer.exe se ferme de temps en temps alors je le redémarre manuellement mais il se referme et ainsi de suite

J ai déja nettoyer mon pc avec avast,ad aware,spybot,ccleaner,a squared,vundo etc... mais toujours le meme probleme.
je pense que le probleme vient d un dll dans system32 car souvent rundll32.exe est lancer au moment ou le probleme surgit.

Logfile of Trend Micro HijackThis v2.0.0 (BETA)
Scan saved at 03:09:01, on 16/05/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Winamp\winamp.exe
C:\WINDOWS\explorer.exe
C:\WINDOWS\system32\msiexec.exe
C:\HiJackThis_v2.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.google.fr/ie
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://www.google.fr
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.fr/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://www.google.fr
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.fr/
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://www.google.fr/ie
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://www.google.fr/keyword/%s
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://www.google.fr/
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Fichiers communs\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: PopUpBlocker ; XpTuner2004 - {49E0E0F0-5C30-11D4-945D-000000000010} - C:\PROGRA~1\SIMONT~1\XP-TUN~1\PopUp.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: (no name) - {8630AF6A-3409-4708-9A04-ED9D00CE5F9E} - (no file)
O2 - BHO: (no name) - {967B6797-4BD2-4D66-B3FC-5DE1BA9FD623} - C:\WINDOWS\system32\nnnnomn.dll
O2 - BHO: (no name) - {C061C694-BC6B-40BB-97AC-0B587AB172C3} - (no file)
O2 - BHO: (no name) - {E2EE5C44-C66D-499d-BEAE-A2A79189A63A} - (no file)
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [!AVG Anti-Spyware] "C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe" /minimized
O4 - HKCU\..\Run: [SuperCopier2.exe] C:\Program Files\SuperCopier2\SuperCopier2.exe
O4 - HKCU\..\Run: [Skype] "C:\Program Files\Skype\Phone\Skype.exe" /nosplash /minimized
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-19\..\RunOnce: [Config] %systemroot%\system32\run.cmd (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19\..\RunOnce: [nlsf] cmd.exe /C move /Y "%SystemRoot%\System32\syssetub.dll" "%SystemRoot%\System32\syssetup.dll" (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19\..\RunOnce: [tscuninstall] %systemroot%\system32\tscupgrd.exe (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\RunOnce: [Config] %systemroot%\system32\run.cmd (User 'SERVICE RÉSEAU')
O4 - HKUS\S-1-5-18\..\RunOnce: [Config] %systemroot%\system32\run.cmd (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\RunOnce: [Config] %systemroot%\system32\run.cmd (User 'Default user')
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\REFIEBAR.DLL
O10 - Unknown file in Winsock LSP: c:\windows\system32\nwprovau.dll
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FICHIE~1\Skype\Skype4COM.dll
O20 - Winlogon Notify: awvvv - C:\WINDOWS\system32\awvvv.dll
O20 - Winlogon Notify: nnnnomn - C:\WINDOWS\SYSTEM32\nnnnomn.dll
O22 - SharedTaskScheduler: Pré-chargeur Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Démon de cache des catégories de composant - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: Acronis Scheduler2 Service (AcrSch2Svc) - Acronis - C:\Program Files\Fichiers communs\Maxtor\Schedule2\schedul2.exe
O23 - Service: Adobe LM Service - Adobe Systems - C:\Program Files\Fichiers communs\Adobe Systems Shared\Service\Adobelmsvc.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: AVG Anti-Spyware Guard - Anti-Malware Development a.s. - C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: Service d'administration du Gestionnaire de disque logique (dmadmin) - Unknown owner - C:\WINDOWS\System32\dmadmin.exe
O23 - Service: Journal des événements (Eventlog) - Unknown owner - C:\WINDOWS\system32\services.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\1150\Intel 32\IDriverT.exe
O23 - Service: LVSrvLauncher - Logitech Inc. - C:\Program Files\Fichiers communs\LogiShrd\SrvLnch\SrvLnch.exe
O23 - Service: DDE réseau (NetDDE) - Unknown owner - C:\WINDOWS\system32\netdde.exe
O23 - Service: DSDM DDE réseau (NetDDEdsdm) - Unknown owner - C:\WINDOWS\system32\netdde.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Plug-and-Play (PlugPlay) - Unknown owner - C:\WINDOWS\system32\services.exe
O23 - Service: Gestionnaire de session d'aide sur le Bureau à distance (RDSessMgr) - Unknown owner - C:\WINDOWS\system32\sessmgr.exe
O23 - Service: Telnet (TlntSvr) - Unknown owner - C:\WINDOWS\system32\tlntsvr.exe
O23 - Service: Cliché instantané de volume (VSS) - Unknown owner - C:\WINDOWS\System32\vssvc.exe
O23 - Service: Service Partage réseau du Lecteur Windows Media (WMPNetworkSvc) - Unknown owner - C:\Program Files\Windows Media Player\WMPNetwk.exe

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