Comment virer le cheval de troie?

Merci pour ta reponse, c'est gentille.
Cordialement, Lubov.

Voici mon rapport:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 21:58:57, on 23/08/2010
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
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\nvsvc32.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\PROGRA~1\ALWILS~1\Avast5\avastUI.exe
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\Google\Quick Search Box\GoogleQuickSearchBox.exe
C:\Program Files\Adobe\Photoshop Album Edition Découverte\3.0\Apps\apdproxy.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\FinePixViewerS\QuickDCF2.exe
C:\Program Files\Hewlett-Packard\Digital Imaging\bin\hpohmr08.exe
C:\Program Files\Hewlett-Packard\Digital Imaging\bin\hpotdd01.exe
C:\Program Files\Hewlett-Packard\Digital Imaging\bin\hpoevm08.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Windows Live Toolbar\msn_sl.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = https://www.bing.com/?FORM=TOOLBR&cc=fr&toHttps=1&redig=4527FFF1C12746FC9EDB535C75E80ECC
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = https://www.bing.com/?FORM=TOOLBR&cc=fr&toHttps=1&redig=4527FFF1C12746FC9EDB535C75E80ECC
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.orange.fr/portail
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.msn.com/fr-fr/?ocid=iehp
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.msn.com/fr-fr/?ocid=iehp
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = https://www.bing.com/?FORM=TOOLBR&cc=fr&toHttps=1&redig=4527FFF1C12746FC9EDB535C75E80ECC
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.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\5.5.5126.1836\swg.dll
O2 - BHO: Windows Live Toolbar Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O3 - Toolbar: Google Toolbar - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - C:\Program Files\Google\Google Toolbar\GoogleToolbar_32.dll
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O4 - HKLM\..\Run: [avast5] C:\PROGRA~1\ALWILS~1\Avast5\avastUI.exe /nogui
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINDOWS\system32\NeroCheck.exe
O4 - HKLM\..\Run: [Google Quick Search Box] "C:\Program Files\Google\Quick Search Box\GoogleQuickSearchBox.exe" /autorun
O4 - HKLM\..\Run: [Adobe Photo Downloader] "C:\Program Files\Adobe\Photoshop Album Edition Découverte\3.0\Apps\apdproxy.exe"
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - Global Startup: Exif Launcher S.lnk = ?
O4 - Global Startup: hp psc 1000 series.lnk = ?
O4 - Global Startup: hpoddt01.exe.lnk = ?
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office\OSA9.EXE
O8 - Extra context menu item: &Windows Live Search - res://C:\Program Files\Windows Live Toolbar\msntb.dll/search.htm
O8 - Extra context menu item: Google Sidewiki... - res://C:\Program Files\Google\Google Toolbar\Component\GoogleToolbarDynamic_mui_en_89D8574934B26AC4.dll/cmsidewiki.html
O17 - HKLM\System\CCS\Services\Tcpip\..\{2B603B48-B4DE-4BE1-89B7-C13216319138}: NameServer = 80.10.246.134 80.10.246.7
O23 - Service: avast! Antivirus - AVAST Software - C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
O23 - Service: avast! Mail Scanner - AVAST Software - C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
O23 - Service: avast! Web Scanner - AVAST Software - C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
O23 - Service: Service Google Update (gupdate) (gupdate) - 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: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: Ma-Config Service (maconfservice) - CybelSoft - C:\Program Files\ma-config.com\maconfservice.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe