Impossible mettre papier peint vista

Bonjour à tous,

suite a des infections de spy et autres virus j' ai du effectuer un nettoyage complet .

seulement depuis plus d' arriere plan.
il m' est impossible d' en mettre un que ce soit par definir en tant que arriere plan ou par le gestionnaire.
d' ailleur pour ce dernier les images n 'apparaissent plus en previsualisation.

je ne peus que changer la couleur de l' arriere plan et c' est tout.

merci de votre aide............

voici un log par hijackthis:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:43, on 2008-04-17
Platform: Windows Vista SP1 (WinNT 6.00.1905)
MSIE: Internet Explorer v7.00 (7.00.6001.18000)
Boot mode: Normal

Running processes:
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Program Files\Windows Defender\MSASCui.exe
C:\Windows\RtHDVCpl.exe
C:\Acer\Empowering Technology\eDataSecurity\eDSLoader.exe
C:\Acer\Empowering Technology\eAudio\eAudio.exe
C:\Windows\system32\taskeng.exe
C:\Users\Fabrice\AppData\Local\Temp\RtkBtMnt.exe
C:\Windows\System32\mobsync.exe
C:\Program Files\Acer Arcade Deluxe\Play Movie\PMVService.exe
C:\Program Files\Apoint2K\Apoint.exe
C:\Program Files\Java\jre1.6.0_05\bin\jusched.exe
C:\Program Files\Nokia\Nokia PC Suite 6\LaunchApplication.exe
C:\Program Files\ScanSoft\OmniPageSE4\OpWareSE4.exe
C:\Windows\WindowsMobile\wmdSync.exe
C:\Windows\System32\rundll32.exe
C:\Program Files\Alwil Software\Avast4\ashDisp.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Windows\ehome\ehtray.exe
C:\Windows\System32\rundll32.exe
C:\Windows\ehome\ehmsas.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Apoint2K\Apntex.exe
C:\Program Files\Windows Live\Messenger\msnmsgr.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Acer\Empowering Technology\ENET\ENMTRAY.EXE
C:\Program Files\OpenOffice.org 2.4\program\soffice.exe
C:\Acer\Empowering Technology\EPOWER\EPOWER_DMC.EXE
C:\Acer\Empowering Technology\ACER.EMPOWERING.FRAMEWORK.SUPERVISOR.EXE
C:\Acer\Empowering Technology\eRecovery\ERAGENT.EXE
C:\Program Files\OpenOffice.org 2.4\program\soffice.BIN
C:\Windows\system32\wbem\unsecapp.exe
C:\Program Files\Internet Explorer\ieuser.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Common Files\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Windows\system32\Macromed\Flash\FlashUtil9b.exe
C:\Users\Fabrice\Desktop\Securitè\test.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr/?gws_rd=ssl
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
R3 - URLSearchHook: Yahoo! Toolbar avec bloqueur de fenêtres pop-up - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O2 - BHO: Yahoo! Toolbar Helper - {02478D38-C3F9-4EFB-9B51-7695ECA05670} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Spybot-S&D IE Protection - {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\jre1.6.0_05\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
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
O3 - Toolbar: Acer eDataSecurity Management - {5CBE3B7C-1E47-477e-A7DD-396DB0476E29} - C:\Windows\system32\eDStoolbar.dll
O3 - Toolbar: Yahoo! Toolbar avec bloqueur de fenêtres pop-up - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [RtHDVCpl] RtHDVCpl.exe
O4 - HKLM\..\Run: [eDataSecurity Loader] C:\Acer\Empowering Technology\eDataSecurity\eDSloader.exe
O4 - HKLM\..\Run: [eAudio] "C:\Acer\Empowering Technology\eAudio\eAudio.exe"
O4 - HKLM\..\Run: [LManager] C:\PROGRA~1\LAUNCH~1\LManager.exe
O4 - HKLM\..\Run: [PlayMovie] "C:\Program Files\Acer Arcade Deluxe\Play Movie\PMVService.exe"
O4 - HKLM\..\Run: [PLFSetL] C:\Windows\PLFSetL.exe
O4 - HKLM\..\Run: [Apoint] C:\Program Files\Apoint2K\Apoint.exe
O4 - HKLM\..\Run: [WarReg_PopUp] C:\Acer\WR_PopUp\WarReg_PopUp.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0_05\bin\jusched.exe"
O4 - HKLM\..\Run: [PCSuiteTrayApplication] C:\Program Files\Nokia\Nokia PC Suite 6\LaunchApplication.exe -startup
O4 - HKLM\..\Run: [SSBkgdUpdate] "C:\Program Files\Common Files\Scansoft Shared\SSBkgdUpdate\SSBkgdupdate.exe" -Embedding -boot
O4 - HKLM\..\Run: [OpwareSE4] "C:\Program Files\ScanSoft\OmniPageSE4\OpwareSE4.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [Windows Mobile-based device management] %windir%\WindowsMobile\wmdSync.exe
O4 - HKLM\..\Run: [NvSvc] RUNDLL32.EXE C:\Windows\system32\nvsvc.dll,nvsvcStart
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\Windows\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\Windows\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [ehTray.exe] C:\Windows\ehome\ehTray.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKUS\S-1-5-18\..\Run: [PcSync] C:\Program Files\Nokia\Nokia PC Suite 6\PcSync2.exe /NoDialog (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [PcSync] C:\Program Files\Nokia\Nokia PC Suite 6\PcSync2.exe /NoDialog (User 'Default user')
O4 - Startup: OpenOffice.org 2.4.lnk = C:\Program Files\OpenOffice.org 2.4\program\quickstart.exe
O4 - Global Startup: Empowering Technology Launcher.lnk = C:\Acer\Empowering Technology\eAPLauncher.exe
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.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
O13 - Gopher Prefix:
O16 - DPF: {30528230-99f7-4bb4-88d8-fa1d4f56a2ab} (YInstStarter Class) - C:\Program Files\Yahoo!\Common\yinsthelper.dll
O23 - Service: ALaunch Service (ALaunchService) - Unknown owner - C:\Acer\ALaunch\ALaunchSvc.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.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: eDSService.exe (eDataSecurity Service) - HiTRSUT - C:\Acer\Empowering Technology\eDataSecurity\eDSService.exe
O23 - Service: eLock Service (eLockService) - Acer Inc. - C:\Acer\Empowering Technology\eLock\Service\eLockServ.exe
O23 - Service: eNet Service - Acer Inc. - C:\Acer\Empowering Technology\eNet\eNet Service.exe
O23 - Service: eRecovery Service (eRecoveryService) - Acer Inc. - C:\Acer\Empowering Technology\eRecovery\eRecoveryService.exe
O23 - Service: eSettings Service (eSettingsService) - Unknown owner - C:\Acer\Empowering Technology\eSettings\Service\capuserv.exe
O23 - Service: PIXMA Extended Survey Program (IJPLMSVC) - Unknown owner - C:\Program Files\Canon\IJPLM\IJPLMSVC.EXE
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - C:\Program Files\Common Files\LightScribe\LSSrvc.exe
O23 - Service: MobilityService - Unknown owner - C:\Acer\Mobility Center\MobilityService.exe
O23 - Service: Planificateur LiveUpdate automatique - Unknown owner - C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe (file missing)
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - C:\Program Files\CyberLink\Shared Files\RichVideo.exe
O23 - Service: SBSD Security Center Service (SBSDWSCService) - Safer Networking Ltd. - C:\Program Files\Spybot - Search & Destroy\SDWinSec.exe
O23 - Service: ServiceLayer - Nokia. - C:\Program Files\PC Connectivity Solution\ServiceLayer.exe
O23 - Service: ePower Service (WMIService) - acer - C:\Acer\Empowering Technology\ePower\ePowerSvc.exe
O23 - Service: XAudioService - Conexant Systems, Inc. - C:\Windows\system32\DRIVERS\xaudio.exe