Problème fentre incomprehensible au démarrage

Bonjour à tous,
un petit coup de main svp pour un petit soucis, au demarrage de mon ordi, une fois sur deux, j'ai un message incompréhensible (avant l'invite d'ouverture de session) qui se présente sous forme d'une fenetre sur fond gris ou je peux juste valider par OK. Les lettres d'en têtes sont illisibles, du charabia...
Je poste un log Hijackthis au cas ou...
Merci de votre aide.
Baptistou

Logfile of HijackThis v1.99.1
Scan saved at 20:56:50, on 06/06/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

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:\WINDOWS\system32\svchost.exe
C:\Program Files\Intel\Wireless\Bin\EvtEng.exe
C:\Program Files\Intel\Wireless\Bin\S24EvMon.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\ATK0100\HControl.exe
C:\Program Files\ASUS\Power4 Gear\BatteryLife.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\Nokia\Nokia PC Suite 6\LaunchApplication.exe
C:\Program Files\ASUS\Wireless Console\wcourier.exe
C:\Program Files\Intel\Wireless\bin\ZCfgSvc.exe
C:\Program Files\Intel\Wireless\Bin\ifrmewrk.exe
C:\Program Files\Fichiers communs\Ahead\Lib\NMBgMonitor.exe
C:\Program Files\Fichiers communs\Ahead\Lib\NMIndexStoreSvr.exe
C:\WINDOWS\ATKKBService.exe
C:\WINDOWS\system32\CTsvcCDA.EXE
C:\Program Files\Sunbelt Software\Personal Firewall\kpf4ss.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\Program Files\Sunbelt Software\Personal Firewall\kpf4gui.exe
C:\Program Files\Intel\Wireless\Bin\RegSrvc.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\ATK0100\ATKOSD.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\Program Files\Sunbelt Software\Personal Firewall\kpf4gui.exe
C:\Program Files\Intel\Wireless\Bin\Dot1XCfg.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Mozilla Thunderbird\thunderbird.exe
C:\WINDOWS\system32\NOTEPAD.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\HijackThis\scanner.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.asus.com/fr/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.asus.com/fr/
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://messenger.msn.com/flash/?mkt=fr-fr&version=9,0,28,0
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.5.0_11\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Fichiers communs\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O4 - HKLM\..\Run: [HControl] C:\WINDOWS\ATK0100\HControl.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [Power_Gear] C:\Program Files\ASUS\Power4 Gear\BatteryLife.exe 1
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [PinnacleDriverCheck] C:\WINDOWS\system32\PSDrvCheck.exe -CheckReg
O4 - HKLM\..\Run: [PCSuiteTrayApplication] C:\Program Files\Nokia\Nokia PC Suite 6\LaunchApplication.exe -startup
O4 - HKLM\..\Run: [Wireless Console] C:\Program Files\ASUS\Wireless Console\wcourier.exe
O4 - HKLM\..\Run: [IntelZeroConfig] "C:\Program Files\Intel\Wireless\bin\ZCfgSvc.exe"
O4 - HKLM\..\Run: [IntelWireless] "C:\Program Files\Intel\Wireless\Bin\ifrmewrk.exe" /tf Intel PROSet/Wireless
O4 - HKCU\..\Run: [BgMonitor_{79662E04-7C6C-4d9f-84C7-88D8A56B10AA}] "C:\Program Files\Fichiers communs\Ahead\Lib\NMBgMonitor.exe"
O4 - Global Startup: Accélérateur de démarrage AutoCAD.lnk = C:\Program Files\Fichiers communs\Autodesk Shared\acstart17.exe
O9 - Extra button: (no name) - {85d1f590-48f4-11d9-9669-0800200c9a66} - %windir%\bdoscandel.exe (file missing)
O9 - Extra 'Tools' menuitem: Uninstall BitDefender Online Scanner v8 - {85d1f590-48f4-11d9-9669-0800200c9a66} - %windir%\bdoscandel.exe (file missing)
O14 - IERESET.INF: START_PAGE_URL=https://www.asus.com/fr/
O16 - DPF: {0A5FD7C5-A45C-49FC-ADB5-9952547D5715} (Creative Software AutoUpdate) - http://www.creative.com/su/ocx/15026/CTSUEng.cab
O16 - DPF: {215B8138-A3CF-44C5-803F-8226143CFC0A} (Trend Micro ActiveX Scan Agent 6.6) - http://eu-housecall.trendmicro-europe.com/housecall/applet/html/native/x86/win32/activex/hcImpl.cab
O16 - DPF: {2917297F-F02B-4B9D-81DF-494B6333150B} (Minesweeper Flags Class) - http://messenger.zone.msn.com/binary/MineSweeper.cab31267.cab
O16 - DPF: {5D86DDB5-BDF9-441B-9E9E-D4730F4EE499} (BDSCANONLINE Control) - http://www.zebulon.fr/scan8/oscan8.cab
O16 - DPF: {6531D99C-0D0E-4293-B3CB-A3E1D0D41847} (AhnASP Control) - http://aspglobal.ahnlab.com/asp/cab/AhnASP.cab
O16 - DPF: {7B297BFD-85E4-4092-B2AF-16A91B2EA103} (WScanCtl Class) - http://www.ca.com/us/securityadvisor/virusinfo/webscan.cab
O16 - DPF: {8E0D4DE5-3180-4024-A327-4DFAD1796A8D} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsClient.cab31267.cab
O16 - DPF: {9A9307A0-7DA4-4DAF-B042-5009F29E09E1} (ActiveScan Installer Class) - http://acs.pandasoftware.com/activescan/as5free/asinst.cab
O16 - DPF: {F6ACF75C-C32C-447B-9BEF-46B766368D29} (Creative Software AutoUpdate Support Package) - http://www.creative.com/su/ocx/15028/CTPID.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{78DEA2F3-F764-4463-9CF2-20A1A43663C1}: NameServer = 192.168.104.1
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O20 - Winlogon Notify: WgaLogon - C:\WINDOWS\SYSTEM32\WgaLogon.dll
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: ATK Keyboard Service (ATKKeyboardService) - ASUSTeK COMPUTER INC. - C:\WINDOWS\ATKKBService.exe
O23 - Service: Autodesk Licensing Service - Autodesk - C:\Program Files\Fichiers communs\Autodesk Shared\Service\AdskScSrv.exe
O23 - Service: avast! Antivirus - ALWIL Software - 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: Creative Service for CDROM Access - Creative Technology Ltd - C:\WINDOWS\system32\CTsvcCDA.EXE
O23 - Service: Intel(R) PROSet/Wireless Event Log (EvtEng) - Intel Corporation - C:\Program Files\Intel\Wireless\Bin\EvtEng.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: Sunbelt Kerio Personal Firewall 4 (KPF4) - Sunbelt Software - C:\Program Files\Sunbelt Software\Personal Firewall\kpf4ss.exe
O23 - Service: NBService - Nero AG - C:\Program Files\Nero\Nero 7\Nero BackItUp\NBService.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Intel(R) PROSet/Wireless Registry Service (RegSrvc) - Intel Corporation - C:\Program Files\Intel\Wireless\Bin\RegSrvc.exe
O23 - Service: Spectrum24 Event Monitor (S24EventMonitor) - Intel Corporation - C:\Program Files\Intel\Wireless\Bin\S24EvMon.exe