Explorer.exe se ferme tout le temps !

Bonsoir,

Voila depuis tout a l'heure j'ai un probleme assez énervant : explorer.exe se ferme tout le temps !
J'ai une fenetre "explorer.exe a rencontré un probleme et doit fermer." qui s'affiche toutes les 5 secondes...
D'où ça vient ?
Voici mon log HijackThis :

Logfile of HijackThis v1.99.1
Scan saved at 19:45:45, on 08/06/2005
Platform: Windows XP SP1 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP1 (6.00.2800.1106)

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\TGTSoft\StyleXP\StyleXPService.exe
C:\WINDOWS\system32\LEXBCES.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\LEXPPS.EXE
C:\Program Files\Lexmark X1100 Series\lxbkbmgr.exe
C:\WINDOWS\System32\sstray.exe
C:\WINDOWS\System32\RUNDLL32.EXE
C:\Program Files\MessengerPlus! 3\MsgPlus.exe
C:\Program Files\Fichiers communs\Real\Update_OB\realsched.exe
C:\Program Files\Messenger\msmsgs.exe
C:\Program Files\Lexmark X1100 Series\lxbkbmon.exe
C:\Program Files\Labtec\Wireless Mouse\MulMouse.exe
C:\WINDOWS\System32\nvsvc32.exe
c:\Program Files\Sophos\Sophos Anti-Virus\SAVAdminService.exe
c:\Program Files\Sophos\AutoUpdate\ALsvc.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\System32\wuauclt.exe
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
C:\Program Files\Grisoft\AVG7\avgemc.exe
C:\Program Files\Grisoft\AVG7\avgcc.exe
C:\Program Files\Alwil Software\Avast4\ashSimpl.exe
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\Program Files\WinRAR\WinRAR.exe
C:\HijackThis.exe
C:\WINDOWS\System32\wuauclt.exe
C:\WINDOWS\system32\NOTEPAD.EXE
C:\WINDOWS\explorer.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = about:blank
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://www.updatesearches.com/search.php?qq=%1
R1 - HKCU\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://www.updatesearches.com/search.php?qq=%1
R1 - HKCU\Software\Microsoft\Internet Explorer\Search,CustomizeSearch = http://www.updatesearches.com/search.php?qq=%1
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page = http://www.updatesearches.com/
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
F2 - REG:system.ini: Shell=explorer.exe, msmsgs.exe
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\System32\msdxm.ocx
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar1.dll
O4 - HKLM\..\Run: [Lexmark X1100 Series] "C:\Program Files\Lexmark X1100 Series\lxbkbmgr.exe"
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\System32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [nForce Tray Options] sstray.exe /r
O4 - HKLM\..\Run: [quntmoxe] c:\windows\system32\quntmoxe.exe
O4 - HKLM\..\Run: [kivjrjmemktlxjegxbljb] C:\WINDOWS\camucwlb.exe
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\System32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [MessengerPlus3] "C:\Program Files\MessengerPlus! 3\MsgPlus.exe"
O4 - HKLM\..\Run: [MSConfig] C:\WINDOWS\PCHealth\HelpCtr\Binaries\MSConfig.exe /auto
O4 - HKLM\..\Run: [AVG7_CC] C:\PROGRA~1\Grisoft\AVG7\avgcc.exe /STARTUP
O4 - HKLM\..\Run: [AVG7_EMC] C:\PROGRA~1\Grisoft\AVG7\avgemc.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKCU\..\Run: [MessengerPlus3] "C:\Program Files\MessengerPlus! 3\MsgPlus.exe" /WinStart
O4 - HKCU\..\Run: [NBJ] "C:\Program Files\Ahead\Nero BackItUp\NBJ.exe"
O4 - Startup: eMule.lnk = C:\Program Files\eChanblard\emule.exe
O4 - Global Startup: Logiciel de la Souris Labtec 2.0.lnk = C:\Program Files\Labtec\Wireless Mouse\MulMouse.exe
O8 - Extra context menu item: Use as &Display Picture - C:\Program Files\IEDP2\IEDP.htm
O9 - Extra button: Trace - {04849C74-016E-4a43-8AA5-1F01DE57F4A1} - C:\Program Files\VisualRoute\vrie.dll
O9 - Extra 'Tools' menuitem: VisualRoute Trace - {04849C74-016E-4a43-8AA5-1F01DE57F4A1} - C:\Program Files\VisualRoute\vrie.dll
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\WINDOWS\System32\msjava.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\WINDOWS\System32\msjava.dll
O9 - Extra button: AIM - {AC9E2541-2814-11d5-BC6D-00B0D0A1DE45} - C:\Program Files\AIM\aim.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\MSMSGS.EXE
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\MSMSGS.EXE
O16 - DPF: A3Cab1 - http://www.globalcashsolutions.com/kithtml/A3Cab1.CAB
O16 - DPF: {14A3221B-1678-1982-A355-7263B1281987} - ms-its:mhtml:file://C:tsk.mht!http://69.50.166.110/5/s1//q.chm::/file.exe
O16 - DPF: {14B87622-7E19-4EA8-93B3-97215F77A6BC} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsPAClient.cab31267.cab
O16 - DPF: {25BC9512-6215-6FB0-5378-4CE87C93D9EB} - http://216.118.71.185/1/rdgFR1828.exe
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://v5.windowsupdate.microsoft.com/v5consumer/V5Controls/en/x86/client/wuweb_site.cab?1110894542593
O16 - DPF: {74D05D43-3236-11D4-BDCD-00C04F9A3B61} (HouseCall Control) - http://a840.g.akamai.net/7/840/537/2004061001/housecall.trendmicro.com/housecall/xscan53.cab
O16 - DPF: {9122D757-5A4F-4768-82C5-B4171D8556A7} (PhotoPickConvert Class) - http://appdirectory.messenger.msn.com/AppDirectory/P4Apps/PhotoSwap/PhtPkMSN.cab
O16 - DPF: {9A9307A0-7DA4-4DAF-B042-5009F29E09E1} (ActiveScan Installer Class) - http://www.pandasoftware.com/activescan/as5/asinst.cab
O16 - DPF: {A1F2F2CE-06AF-483C-9F12-D3BAA72477D6} (BatchDownloader Class) - http://appdirectory.messenger.msn.com/AppDirectory/P4Apps/PhotoSwap/DigWXMSN.cab
O16 - DPF: {B38870E4-7ECB-40DA-8C6A-595F0A5519FF} (MsnMessengerSetupDownloadControl Class) - http://messenger.msn.com/download/msnmessengersetupdownloader.cab
O16 - DPF: {B8BE5E93-A60C-4D26-A2DC-220313175592} (ZoneIntro Class) - http://messenger.zone.msn.com/binary/ZIntro.cab32846.cab
O20 - Winlogon Notify: style2 - C:\WINDOWS\q111748593_disk.dll
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - Unknown owner - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe" /service (file missing)
O23 - Service: avast! Web Scanner - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe" /service (file missing)
O23 - Service: AVG7 Alert Manager Server (Avg7Alrt) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
O23 - Service: AVG7 Update Service (Avg7UpdSvc) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
O23 - Service: LexBce Server (LexBceS) - Lexmark International, Inc. - C:\WINDOWS\system32\LEXBCES.EXE
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\System32\nvsvc32.exe
O23 - Service: Créateur de rapports d'état Sophos Anti-Virus (SAVAdminService) - Sophos plc - c:\Program Files\Sophos\Sophos Anti-Virus\SAVAdminService.exe
O23 - Service: Sophos Anti-Virus (SAVService) - Sophos plc - c:\Program Files\Sophos\Sophos Anti-Virus\SavService.exe
O23 - Service: Sophos AutoUpdate Service - Sophos plc - c:\Program Files\Sophos\AutoUpdate\ALsvc.exe
O23 - Service: StyleXPService - Unknown owner - C:\Program Files\TGTSoft\StyleXP\StyleXPService.exe

Merci.