Trojan system32\boi.exe

Bonjour,
symantec antivirus m'affiche sans cesse un message d'alerte pour un trojan, je n'arrive pas a le supprimer, que dois-je faire?
merci d'avance!

voici le rapport de hijackthis:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 22:44:47, on 16/04/2009
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16791)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\csrss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\ATI Technologies\ATI.ACE\CLI.EXE
C:\WINDOWS\RTHDCPL.EXE
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\Toshiba\Toshiba Applet\thotkey.exe
C:\WINDOWS\system32\TPSMain.exe
C:\PROGRA~1\SYMANT~1\SYMANT~1\vptray.exe
C:\Program Files\iTunes\iTunesHelper.exe
C:\Program Files\Synaptics\SynTP\Toshiba.exe
C:\Program Files\Java\jre6\bin\jusched.exe
C:\WINDOWS\system32\boi.exe
C:\WINDOWS\system32\TPSBattM.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\TOSHIBA\TOSCDSPD\toscdspd.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Program Files\Fichiers communs\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\Program Files\Bonjour\mDNSResponder.exe
C:\PROGRA~1\SYMANT~1\SYMANT~1\DefWatch.exe
C:\WINDOWS\system32\DVDRAMSV.exe
C:\Program Files\Java\jre6\bin\jqs.exe
C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
C:\Program Files\Fichiers communs\Microsoft Shared\VS7DEBUG\mdm.exe
C:\PROGRA~1\SYMANT~1\SYMANT~1\Rtvscan.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\TOSHIBA\TOSHIBA Applet\TAPPSRV.exe
C:\Program Files\Toshiba\Bluetooth Toshiba Stack\TosBtSrv.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\WINDOWS\system32\wbem\wmiapsrv.exe
C:\WINDOWS\System32\alg.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\Program Files\Fichiers communs\Adobe\Updater6\Adobe_Updater.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\hijackthis\eden.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.facebook.com/login.php?next=https%3A%2F%2Fwww.facebook.com%2Fhome.php
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\Windows\CurrentVersion\Internet Settings,ProxyOverride = *.local
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
F2 - REG:system.ini: UserInit=C:\WINDOWS\system32\userinit.exe,C:\Documents and Settings\Benjamin\iqygxs.exe \s
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files\Fichiers communs\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6f74-2d53-2644-206d7942484f} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: Programme d'aide de l'Assistant de connexion Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Fichiers communs\Microsoft Shared\Windows Live\WindowsLiveLogin.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: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - C:\Program Files\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O3 - Toolbar: Easy-WebPrint - {327C2873-E90D-4c37-AA9D-10AC9BABA46C} - C:\Program Files\Canon\Easy-WebPrint\Toolband.dll
O4 - HKLM\..\Run: [ATICCC] "C:\Program Files\ATI Technologies\ATI.ACE\CLIStart.exe"
O4 - HKLM\..\Run: [RTHDCPL] RTHDCPL.EXE
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [THotkey] C:\Program Files\Toshiba\Toshiba Applet\thotkey.exe
O4 - HKLM\..\Run: [TPSMain] TPSMain.exe
O4 - HKLM\..\Run: [vptray] C:\PROGRA~1\SYMANT~1\SYMANT~1\vptray.exe
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre6\bin\jusched.exe"
O4 - HKLM\..\Run: [boi] C:\WINDOWS\system32\boi.exe \u
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [TOSCDSPD] C:\Program Files\TOSHIBA\TOSCDSPD\toscdspd.exe
O4 - HKCU\..\Run: [Wallpaper] "C:\Program Files\Wallpaper\Wallpaper.exe" Starter
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: Easy-WebPrint Ajouter à la liste d'impressions - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_AddToList.html
O8 - Extra context menu item: Easy-WebPrint Impression rapide - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_HSPrint.html
O8 - Extra context menu item: Easy-WebPrint Imprimer - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_Print.html
O8 - Extra context menu item: Easy-WebPrint Prévisualiser - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_Preview.html
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\REFIEBAR.DLL
O9 - Extra button: (no name) - {dfb852a3-47f8-48c4-a200-58cab36fd2a2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {dfb852a3-47f8-48c4-a200-58cab36fd2a2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.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: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://update.microsoft.com/...
O16 - DPF: {8AD9C840-044E-11D1-B3E9-00805F499D93} (Java Runtime Environment 1.6.0) - http://dl8-cdn-01.sun.com/s/ESD7/JSCDL/jdk/6u12-b04/jinstall-6u12-windows-i586-jc.cab?e=1235520086451&h=e32514d84a9c9bc41a43e029c4cc7c65/&filename=jinstall-6u12-windows-i586-jc.cab
O23 - Service: Adobe LM Service - Adobe Systems - C:\Program Files\Fichiers communs\Adobe Systems Shared\Service\Adobelmsvc.exe
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Program Files\Fichiers communs\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: Service de transfert intelligent en arrière-plan (BITS) - Unknown owner - C:\WINDOWS\
O23 - Service: Service Bonjour (Bonjour Service) - Apple Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: DefWatch - Symantec Corporation - C:\PROGRA~1\SYMANT~1\SYMANT~1\DefWatch.exe
O23 - Service: DVD-RAM_Service - Matsushita Electric Industrial Co., Ltd. - C:\WINDOWS\system32\DVDRAMSV.exe
O23 - Service: Service de l’iPod (iPod Service) - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Sun Microsystems, Inc. - C:\Program Files\Java\jre6\bin\jqs.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Unknown owner - C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
O23 - Service: Symantec AntiVirus Client (Norton AntiVirus Server) - Symantec Corporation - C:\PROGRA~1\SYMANT~1\SYMANT~1\Rtvscan.exe
O23 - Service: PC Tools Auxiliary Service (sdauxservice) - PC Tools - C:\Program Files\Spyware Doctor\pctsAuxs.exe
O23 - Service: PC Tools Security Service (sdcoreservice) - PC Tools - C:\Program Files\Spyware Doctor\pctsSvc.exe
O23 - Service: TOSHIBA Application Service (TAPPSRV) - TOSHIBA Corp. - C:\Program Files\TOSHIBA\TOSHIBA Applet\TAPPSRV.exe
O23 - Service: TOSHIBA Bluetooth Service - TOSHIBA CORPORATION - C:\Program Files\Toshiba\Bluetooth Toshiba Stack\TosBtSrv.exe
O23 - Service: Mises à jour automatiques (wuauserv) - Unknown owner - C:\WINDOWS\