Trojan!

Salut tout le monde, depuis quelque jours mon PC est infecté par un cheval de Troie s'appellant Trojan.Win32.Zapchast.dt,
mon antivirus (orange) le detecte, me propose de le supprimer, le "supprime" mais le virus revient toujours et on me repropose de le supprimer, etc...
Il est dans C:\WINDOWS\SYSTEM32\WINDOWS. Mon systeme est un FAT32.
Voila je ne peut pas vous donner plus de précisions,
Voici le rapport HiJack This:

Logfile of HijackThis v1.99.1
Scan saved at 14:59:04, on 20/02/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16608)

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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\PROGRA~1\ANTIVI~1\backweb\6588780\Program\SERVIC~1.EXE
C:\WINDOWS\System32\drivers\CDAC11BA.EXE
C:\Program Files\AntivirusFirewall\Anti-Virus\fsgk32st.exe
C:\Program Files\AntivirusFirewall\Anti-Virus\FSGK32.EXE
C:\Program Files\AntivirusFirewall\Anti-Virus\fssm32.exe
C:\Program Files\AntivirusFirewall\backweb\6588780\program\fsbwsys.exe
C:\Program Files\AntivirusFirewall\Common\FSMA32.EXE
C:\WINDOWS\System32\FTRTSVC.exe
C:\Program Files\AntivirusFirewall\Common\FSMB32.EXE
C:\WINDOWS\system32\drivers\KodakCCS.exe
C:\Program Files\AntivirusFirewall\Common\FCH32.EXE
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\System32\UAService7.exe
C:\Program Files\AntivirusFirewall\Common\FAMEH32.EXE
C:\Program Files\AntivirusFirewall\Anti-Virus\fsqh.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\Program Files\AntivirusFirewall\Anti-Virus\fsrw.exe
C:\Program Files\AntivirusFirewall\Anti-Virus\fsav32.exe
C:\Program Files\AntivirusFirewall\FWES\Program\fsdfwd.exe
C:\PROGRA~1\ANTIVI~1\ANTI-S~1\fsaw.exe
C:\PROGRA~1\WANADOO\TaskBarIcon.exe
C:\Program Files\AntivirusFirewall\FSGUI\ispnews.exe
C:\Program Files\Fichiers communs\Real\Update_OB\realsched.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\Program Files\AntivirusFirewall\FSGUI\fsguidll.exe
C:\Program Files\6\SysRep.exe
C:\WINDOWS\system32\rundll32.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\MSN Messenger\msnmsgr.exe
C:\Program Files\AntivirusFirewall\backweb\6588780\Program\fspex.exe
C:\PROGRA~1\WANADOO\GestionnaireInternet.exe
C:\PROGRA~1\WANADOO\ComComp.exe
C:\PROGRA~1\WANADOO\Toaster.exe
C:\PROGRA~1\WANADOO\Inactivity.exe
C:\PROGRA~1\WANADOO\PollingModule.exe
C:\WINDOWS\System32\ALERTM~1\ALERTM~1.EXE
C:\PROGRA~1\WANADOO\Watch.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\WINDOWS\explorer.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\WinRAR\WinRAR.exe
C:\WINDOWS\system32\wuauclt.exe
C:\DOCUME~1\Sacha\LOCALS~1\Temp\Rar$EX11.7719\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://home.neuf.fr
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = https://actus.sfr.fr
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = https://actus.sfr.fr
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.ustart.org
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://actus.sfr.fr
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 = http://www.ustart.org
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = https://actus.sfr.fr
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Orange
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
R3 - URLSearchHook: Multi Media Toolbar - {b5146c40-189a-4311-bda9-fbae3e023187} - C:\Program Files\Multi_Media\tbMult.dll
R3 - URLSearchHook: Search Class - {08C06D61-F1F3-4799-86F8-BE1A89362C85} - C:\PROGRA~1\WANADOO\SEARCH~1.DLL
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O3 - Toolbar: H&otbar - {74CC49F7-EB32-4A08-B204-948962A6E3DB} - C:\Program Files\HbTools\Bin\4.8.2.0\HbtHostIE.dll (file missing)
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O3 - Toolbar: Multi Media Toolbar - {b5146c40-189a-4311-bda9-fbae3e023187} - C:\Program Files\Multi_Media\tbMult.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar3.dll
O3 - Toolbar: EPSON Web-To-Page - {EE5D279F-081B-4404-994D-C6B60AAEBA6D} - C:\Program Files\EPSON\EPSON Web-To-Page\EPSON Web-To-Page.dll (file missing)
O4 - HKLM\..\Run: [UserFaultCheck] %systemroot%\system32\dumprep 0 -u
O4 - HKLM\..\Run: [WOOWATCH] C:\PROGRA~1\WANADOO\Watch.exe
O4 - HKLM\..\Run: [WOOTASKBARICON] C:\PROGRA~1\WANADOO\GestMaj.exe TaskBarIcon.exe
O4 - HKLM\..\Run: [F-Secure Manager] "C:\Program Files\AntivirusFirewall\Common\FSM32.EXE" /splash
O4 - HKLM\..\Run: [F-Secure TNB] "C:\Program Files\AntivirusFirewall\TNB\TNBUtil.exe" /CHECKALL /WAITFORSW
O4 - HKLM\..\Run: [F-Secure Startup Wizard] "C:\Program Files\AntivirusFirewall\FSGUI\FSSW.EXE" /reboot
O4 - HKLM\..\Run: [News Service] "C:\Program Files\AntivirusFirewall\FSGUI\ispnews.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [TkBellExe] "C:\Program Files\Fichiers communs\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [ATICCC] "C:\Program Files\ATI Technologies\ATI.ACE\cli.exe" runtime -Delay
O4 - HKLM\..\Run: [6] C:\Program Files\6\SysRep.exe
O4 - HKLM\..\Run: [2b1b13ad] rundll32.exe "C:\WINDOWS\system32\uodyfidt.dll",b
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [WOOKIT] C:\PROGRA~1\WANADOO\Shell.exe appLaunchClientZone.shl|PARAM= cnx
O4 - HKCU\..\Run: [msnmsgr] "C:\Program Files\MSN Messenger\msnmsgr.exe" /background
O4 - HKCU\..\Run: [RayV] C:\Program Files\RayV\RayV\RayV.exe /background
O4 - Global Startup: Antivirus Firewall.lnk = C:\Program Files\AntivirusFirewall\backweb\6588780\Program\fspex.exe
O8 - Extra context menu item: &Bloquer cette fenêtre publicitaire - C:\Program Files\AntivirusFirewall\Anti-Spyware\blockpopups.htm
O8 - Extra context menu item: &Windows Live Search - res://C:\Program Files\Windows Live Toolbar\msntb.dll/search.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra button: Protection Internet Explorer - {300DB664-75B5-47c0-8B45-A44ACCF73C00} - C:\Program Files\AntivirusFirewall\Anti-Spyware\ieshield.dll
O9 - Extra 'Tools' menuitem: Protection Internet Explorer... - {300DB664-75B5-47c0-8B45-A44ACCF73C00} - C:\Program Files\AntivirusFirewall\Anti-Spyware\ieshield.dll
O9 - Extra button: (no name) - {B205A35E-1FC4-4CE3-818B-899DBBB3388C} - C:\Program Files\Fichiers communs\Microsoft Shared\Encarta Search Bar\ENCSBAR.DLL
O9 - Extra button: ShopperReports - Compare product prices - {C5428486-50A0-4a02-9D20-520B59A9F9B2} - C:\Program Files\ShoppingReport\Bin\2.0.24\ShoppingReport.dll
O9 - Extra button: ShopperReports - Compare travel rates - {C5428486-50A0-4a02-9D20-520B59A9F9B3} - C:\Program Files\ShoppingReport\Bin\2.0.24\ShoppingReport.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra button: Messager Wanadoo - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\PROGRA~1\MESSAG~1\Messager Wanadoo.exe
O9 - Extra 'Tools' menuitem: Messager Wanadoo - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\PROGRA~1\MESSAG~1\Messager Wanadoo.exe
O9 - Extra button: Orange - {1462651F-F4BA-4C76-A001-C4284D0FE16E} - https://www.orange.fr/portail (file missing) (HKCU)
O11 - Options group: [INTERNATIONAL] International*
O15 - Trusted Zone: http://www.redshift.maris.com
O16 - DPF: {00B71CFB-6864-4346-A978-C0A14556272C} (Checkers Class) - http://messenger.zone.msn.com/binary/msgrchkr.cab31267.cab
O16 - DPF: {0878F049-D33E-45E0-A157-C36A6683CF25} - http://es6-scripts.dlv4.com/binaries/egaccess4/egaccess4_1063_XP.cab
O16 - DPF: {09CC593B-E8A9-4491-927D-A3E33534DDD4} (InstallerObj Class) - http://www.m6video.fr/1click/install/files/installer2.cab
O16 - DPF: {1CD4E2DC-2DA0-4154-8723-38CB04FB6A58} - http://scripts.dlv4.com/binaries/egaccess4/egaccess4_1062_XP.cab
O16 - DPF: {4F1E5B1A-2A80-42CA-8532-2D05CB959537} (MSN Photo Upload Tool) - http://gfx1.hotmail.com/mail/w2/resources/MSNPUpld.cab
O16 - DPF: {5054F860-748D-4840-B7B4-DDDB428421AF} (phoneaccess Class) - http://ipdata.phoneaccess.com/dialer/1/cab/fr/phoneaccess.cab
O16 - DPF: {56336BCB-3D8A-11D6-A00B-0050DA18DE71} (RdxIE Class) - http://software-dl.real.com/047ed3c5c9645dfb2414/netzip/RdxIE601_fr.cab
O16 - DPF: {5D6F45B3-9043-443D-A792-115447494D24} (UnoCtrl Class) - http://messenger.zone.msn.com/FR-FR/a-UNO1/GAME_UNO1.cab
O16 - DPF: {67DABFBF-D0AB-41FA-9C46-CC0F21721616} (DivXBrowserPlugin Object) - http://download.divx.com/player/DivXBrowserPlugin.cab
O16 - DPF: {6A060448-60F9-11D5-A6CD-0002B31F7455} (ExentInf Class) -
O16 - DPF: {71DA2A4E-ACB3-4065-9E41-8BC42EABE427} - http://scripts.dlv4.com/binaries/IA/svcia32_FR_XP.cab
O16 - DPF: {82FC4503-8459-4239-9B85-0617BEAA950A} - http://es6-scripts.dlv4.com/binaries/egaccess4/egaccess4_1061_XP.cab
O16 - DPF: {8C875948-9C60-4381-9248-0DF180542D53} (HbtInstObj) - http://installs.hotbar.com/installs/hbtools/programs/hbtools.cab
O16 - DPF: {8E0D4DE5-3180-4024-A327-4DFAD1796A8D} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsClient.cab31267.cab
O16 - DPF: {C3F79A2B-B9B4-4A66-B012-3EE46475B072} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsPAClient.cab56907.cab
O16 - DPF: {CB5D474E-A510-40A4-B5A4-838933BCBA64} - http://es6-scripts.dlv4.com/binaries/egaccess4/egaccess4_1065_XP.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O16 - DPF: {E68718BB-5451-4F6F-B8B8-41B4AB672747} (IgbInstall Class) - http://www.internetgamebox.com/content/AxInst.cab
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
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: ATI Smart - Unknown owner - C:\WINDOWS\system32\ati2sgag.exe
O23 - Service: Antivirus Firewall (BackWeb Plug-in - 6588780) - Securitoo Portal - C:\PROGRA~1\ANTIVI~1\backweb\6588780\Program\SERVIC~1.EXE
O23 - Service: Boonty Games - BOONTY - C:\Program Files\Fichiers communs\BOONTY Shared\Service\Boonty.exe
O23 - Service: C-DillaCdaC11BA - Macrovision - C:\WINDOWS\System32\drivers\CDAC11BA.EXE
O23 - Service: FSGKHS (F-Secure Gatekeeper Handler Starter) - F-Secure Corporation - C:\Program Files\AntivirusFirewall\Anti-Virus\fsgk32st.exe
O23 - Service: fsbwsys - F-Secure Corp. - C:\Program Files\AntivirusFirewall\backweb\6588780\program\fsbwsys.exe
O23 - Service: F-Secure Anti-Virus Firewall Daemon (FSDFWD) - F-Secure Corporation - C:\Program Files\AntivirusFirewall\FWES\Program\fsdfwd.exe
O23 - Service: F-Secure Management Agent (FSMA) - F-Secure Corporation - C:\Program Files\AntivirusFirewall\Common\FSMA32.EXE
O23 - Service: France Telecom Routing Table Service (FTRTSVC) - France Telecom - C:\WINDOWS\System32\FTRTSVC.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: Kodak Camera Connection Software (KodakCCS) - Eastman Kodak Company - C:\WINDOWS\system32\drivers\KodakCCS.exe
O23 - Service: SecuROM User Access Service (V7) (UserAccess7) - Unknown owner - C:\WINDOWS\System32\UAService7.exe

Voila, merci pour votre aide!

Configuration: Windows XP
Mozilla 1.7.7