Comment se débarrasser d'un trojan svp?

Bonjour,
J'ai un gros problème avec un certain "trojan-PSW.win32.agent.owa", j'ai fais plusieurs analyses avec avast, trojan remover et malwarebytes, et je n'arrive pas à trouver ce satané cheval de troie! je ne suis pas très doué en informatique mais j'ai quand même le rapport hijackthis:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 12:05:34, on 12/01/2010
Platform: Windows Vista SP2 (WinNT 6.00.1906)
MSIE: Internet Explorer v8.00 (8.00.6001.18865)
Boot mode: Normal

Running processes:
C:\Program Files\Dell\DellDock\DellDock.exe
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Windows\system32\conime.exe
C:\Windows\system32\taskeng.exe
C:\Windows\System32\mobsync.exe
C:\Program Files\Windows Defender\MSASCui.exe
C:\Windows\RtHDVCpl.exe
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\MOM.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\Alwil Software\Avast4\ashDisp.exe
C:\Program Files\Java\jre6\bin\jusched.exe
C:\Program Files\ScanSoft\PaperPort\pptd40nt.exe
C:\Program Files\Brother\Brmfcmon\BrMfcWnd.exe
C:\Program Files\Dell Support Center\bin\sprtcmd.exe
C:\Program Files\OrangeHSS\Launcher\Launcher.exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Program Files\Brother\ControlCenter3\brccMCtl.exe
C:\Program Files\Orange\Telephone sur PC\TelephoneSurPCAgent.exe
C:\Program Files\Brother\Brmfcmon\BrMfcmon.exe
C:\Program Files\Windows Media Player\wmpnscfg.exe
C:\Windows\System32\rundll32.exe
C:\Program Files\OpenOffice.org 2.4\program\soffice.exe
C:\PROGRA~1\COMMON~1\France Telecom\Shared Modules\AlertModule\0\AlertModule.exe
C:\Program Files\OpenOffice.org 2.4\program\soffice.BIN
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\CCC.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\OrangeHSS\systray\systrayapp.exe
C:\Program Files\OrangeHSS\connectivity\connectivitymanager.exe
C:\Program Files\OrangeHSS\connectivity\CoreCom\CoreCom.exe
C:\Program Files\OrangeHSS\connectivity\CoreCom\OraConfigRecover.exe
C:\PROGRA~1\COMMON~1\France Telecom\Shared Modules\FTCOMModule\0\FTCOMModule.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Users\Julien\Downloads\HiJackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://www.google.fr/ig/dell?hl=fr&client=dell-row&channel=fr&ibd=2081006
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://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
R3 - URLSearchHook: Search Class - {08C06D61-F1F3-4799-86F8-BE1A89362C85} - C:\Program Files\OrangeHSS\SearchURLHook\SearchPageURL.dll
O1 - Hosts: ::1 localhost
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - c:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: Search Helper - {6EBF7485-159F-4bff-A14F-B9E3AAC4465B} - C:\Program Files\Microsoft\Search Enhancement Pack\Search Helper\SEPsearchhelperie.dll
O2 - BHO: Programme d'aide de l'Assistant de connexion Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - C:\Program Files\Google\Google Toolbar\GoogleToolbar_32.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\5.4.4525.1752\swg.dll
O2 - BHO: Browser Address Error Redirector - {CA6319C0-31B7-401E-A518-A07C3DB8F777} - C:\Program Files\Dell\BAE\BAE.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files\Java\jre6\bin\jp2ssv.dll
O2 - BHO: Windows Live Toolbar Helper - {E15A8DC0-8516-42A1-81EA-DC94EC1ACF10} - C:\Program Files\Windows Live\Toolbar\wltcore.dll
O3 - Toolbar: &Windows Live Toolbar - {21FA44EF-376D-4D53-9B0F-8A89D3229068} - C:\Program Files\Windows Live\Toolbar\wltcore.dll
O3 - Toolbar: Google Toolbar - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - C:\Program Files\Google\Google Toolbar\GoogleToolbar_32.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [ECenter] C:\Dell\E-Center\EULALauncher.exe
O4 - HKLM\..\Run: [RtHDVCpl] RtHDVCpl.exe
O4 - HKLM\..\Run: [StartCCC] "C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\CLIStart.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "c:\Program Files\Adobe\Reader 9.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [Google Desktop Search] "C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe" /startup
O4 - HKLM\..\Run: [dscactivate] "C:\Program Files\Dell Support Center\gs_agent\custom\dsca.exe"
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre6\bin\jusched.exe"
O4 - HKLM\..\Run: [SSBkgdUpdate] "C:\Program Files\Common Files\Scansoft Shared\SSBkgdUpdate\SSBkgdupdate.exe" -Embedding -boot
O4 - HKLM\..\Run: [PaperPort PTD] "C:\Program Files\ScanSoft\PaperPort\pptd40nt.exe"
O4 - HKLM\..\Run: [IndexSearch] "C:\Program Files\ScanSoft\PaperPort\IndexSearch.exe"
O4 - HKLM\..\Run: [PPort11reminder] "C:\Program Files\ScanSoft\PaperPort\Ereg\Ereg.exe" -r "C:\ProgramData\ScanSoft\PaperPort\11\Config\Ereg\Ereg.ini
O4 - HKLM\..\Run: [BrMfcWnd] C:\Program Files\Brother\Brmfcmon\BrMfcWnd.exe /AUTORUN
O4 - HKLM\..\Run: [ControlCenter3] C:\Program Files\Brother\ControlCenter3\brctrcen.exe /autorun
O4 - HKLM\..\Run: [ORAHSSSessionManager] "C:\Program Files\OrangeHSS\SessionManager\SessionManager.exe"
O4 - HKLM\..\Run: [DellSupportCenter] "C:\Program Files\Dell Support Center\bin\sprtcmd.exe" /P DellSupportCenter
O4 - HKCU\..\Run: [DellSupportCenter] "C:\Program Files\Dell Support Center\bin\sprtcmd.exe" /P DellSupportCenter
O4 - HKCU\..\Run: [swg] "C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe"
O4 - HKCU\..\Run: [TELEPHONESURPCAGENT] C:\Program Files\Orange\Telephone sur PC\TelephoneSurPCAgent.exe C:\Program Files\Orange\Telephone sur PC\TelephoneSurPCAgent.exe
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - HKCU\..\Run: [Yahoomsmgr.exe] C:\Windows\system32\rundll32.exe C:\Users\Julien\AppData\Local\Temp\2430ymg.dll,Start
O4 - .DEFAULT User Startup: Dell Dock First Run.lnk = C:\Program Files\Dell\DellDock\DellDock.exe (User 'Default user')
O4 - Startup: Dell Dock.lnk = C:\Program Files\Dell\DellDock\DellDock.exe
O4 - Startup: OpenOffice.org 2.4.lnk = C:\Program Files\OpenOffice.org 2.4\program\quickstart.exe
O8 - Extra context menu item: Google Sidewiki... - res://C:\Program Files\Google\Google Toolbar\Component\GoogleToolbarDynamic_mui_en_60D6097707281E79.dll/cmsidewiki.html
O9 - Extra button: Ajout Direct - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra 'Tools' menuitem: &Ajout Direct dans Windows Live Writer - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files\Windows Live\Writer\WriterBrowserExtension.dll
O13 - Gopher Prefix:
O15 - Trusted Zone: http://*.mappy.com
O15 - Trusted Zone: http://*.orange.fr
O15 - Trusted Zone: http://rw.search.ke.voila.fr
O15 - Trusted Zone: http://orange.weborama.fr
O16 - DPF: {9DF1C00D-8426-4337-972C-DC042D19A916} (FTMediaPlayer Class) - http://webtv.guidetv.orange.fr/resources/OCS_8971.cab
O20 - AppInit_DLLs: C:\PROGRA~1\Google\GOOGLE~2\GOEC62~1.DLL
O20 - Winlogon Notify: GoToAssist - C:\Program Files\Citrix\GoToAssist\514\G2AWinLogon.dll
O23 - Service: Andrea RT Filters Service (AERTFilters) - Andrea Electronics Corporation - C:\Windows\system32\AERTSrv.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: Ati External Event Utility - ATI Technologies Inc. - C:\Windows\system32\Ati2evxx.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: Dock Login Service (DockLoginService) - Stardock Corporation - C:\Program Files\Dell\DellDock\DockLogin.exe
O23 - Service: France Telecom Routing Table Service (FTRTSVC) - France Telecom SA - C:\PROGRA~1\COMMON~1\France Telecom\Shared Modules\FTRTSVC\0\FTRTSVC.exe
O23 - Service: Google Desktop Manager 5.7.801.7324 (GoogleDesktopManager-010708-104812) - Google - C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
O23 - Service: GoToAssist - Citrix Online, a division of Citrix Systems, Inc. - C:\Program Files\Citrix\GoToAssist\514\g2aservice.exe
O23 - Service: Service Google Update (gupdate1ca66ab79bf76d9) (gupdate1ca66ab79bf76d9) - Google Inc. - C:\Program Files\Google\Update\GoogleUpdate.exe
O23 - Service: Google Software Updater (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: SupportSoft Sprocket Service (dellsupportcenter) (sprtsvc_dellsupportcenter) - SupportSoft, Inc. - C:\Program Files\Dell Support Center\bin\sprtsvc.exe