Perdu mon statut "host" ???

Bonjour, jai attraper je ne sais comment un virus quelconque qui fait que jai perdu mon statut de "host".
Par exemple, lorsque j'ai fait un scan HiJackThis, voila ce qui sest produit :

une pop up avec écrit :

For some reason your system denied write access to hosts files. If any hijacked domains are in this file, HijackThis MAY not be able to fix this.
If that happens, you need to edit the file yourself. To do this, click start, Run and type :
notepad C:\Windows\System32\drivers\etc\hosts

and press enter. Find the line(s) Hijackthis reports and delete them.
Save the file as "hosts." (with quotes), and reboot.

Je comprends absolument pas quoi faire mais c'est vraiment fachant et stressant surtout que j'ai beaucoup de documents importants sur l'ordinateur.
Jai tout de même passer un Hijackthis, je vais le coller.
Jai également fait rouler smitfraudfix, je vous colle le rapport dans le prochain post.
merci

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 01:37:22, on 2009-10-23
Platform: Windows Vista SP1 (WinNT 6.00.1905)
MSIE: Internet Explorer v7.00 (7.00.6001.18319)
Boot mode: Safe mode

Running processes:
C:\Windows\Explorer.EXE
C:\Windows\system32\wbem\unsecapp.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.starbarsearch.com/?useie5=1&q=
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://ca.rd.yahoo.com/customize/ie/defaults/sp/msgr9/*https://ca.search.yahoo.com/
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://ca.yahoo.com/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://ca.yahoo.com/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://ca.rd.yahoo.com/customize/ie/defaults/su/msgr9/*https://ca.search.yahoo.com/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.starbarsearch.com/?useie5=1&q=
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://ca.rd.yahoo.com/customize/ie/defaults/sp/msgr9/*https://ca.search.yahoo.com/
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://ca.yahoo.com/
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://ca.rd.yahoo.com/customize/ie/defaults/su/msgr9/*https://ca.search.yahoo.com/
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = *.local
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O2 - BHO: (no name) - {02478D38-C3F9-4efb-9B51-7695ECA05670} - (no file)
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Java(tm) Plug-In SSV Helper - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre6\bin\ssv.dll
O2 - BHO: ShowBarObj Class - {83A2F9B1-01A2-4AA5-87D1-45B6B8505E96} - C:\Windows\system32\ActiveToolBand.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: Star - {B1DA0AEB-85DF-4CE2-B9EE-E23F35D18FF8} - C:\Windows\system32\5778.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files\Java\jre6\bin\jp2ssv.dll
O3 - Toolbar: Acer eDataSecurity Management - {5CBE3B7C-1E47-477e-A7DD-396DB0476E29} - C:\Windows\system32\eDStoolbar.dll
O3 - Toolbar: Star - {B1DA0AEA-85DF-4CE2-B9EE-E23F35D18FF8} - C:\Windows\system32\5778.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [SynTPStart] C:\Program Files\Synaptics\SynTP\SynTPStart.exe
O4 - HKLM\..\Run: [eAudio] "C:\Acer\Empowering Technology\eAudio\eAudio.exe"
O4 - HKLM\..\Run: [LManager] C:\PROGRA~1\LAUNCH~1\QtZgAcer.EXE
O4 - HKLM\..\Run: [egui] "C:\Program Files\ESET\ESET NOD32 Antivirus\egui.exe" /hide /waitservice
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre6\bin\jusched.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\QTTask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [Windows System Defender] "C:\ProgramData\23e65\WS902.exe" /s /d
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [ehTray.exe] C:\Windows\ehome\ehTray.exe
O4 - HKCU\..\Run: [Gestionnaire Antidote.exe] C:\Program Files\Druide\Antidote\Gestionnaire Antidote.exe
O4 - HKCU\..\Run: [AlcoholAutomount] "C:\Program Files\Alcohol Soft\Alcohol 120\axcmd.exe" /automount
O4 - HKCU\..\Run: [OM2_Monitor] "C:\Program Files\OLYMPUS\OLYMPUS Master 2\MMonitor.exe" -NoStart
O4 - HKCU\..\Run: [Speech Recognition] "C:\Windows\Speech\Common\sapisvr.exe" -SpeechUX -Startup
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - HKCU\..\Run: [uTorrent] "C:\Program Files\uTorrent\uTorrent.exe"
O4 - HKCU\..\Run: [Search Protection] C:\Program Files\Yahoo!\Search Protection\SearchProtection.exe
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\REFIEBAR.DLL
O13 - Gopher Prefix:
O23 - Service: ALaunch Service (ALaunchService) - Unknown owner - C:\Acer\ALaunch\ALaunchSvc.exe
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: Service Bonjour (Bonjour Service) - Apple Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: Symantec Lic NetConnect service (CLTNetCnService) - Unknown owner - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe (file missing)
O23 - Service: eDSService.exe (eDataSecurity Service) - HiTRSUT - C:\Acer\Empowering Technology\eDataSecurity\eDSService.exe
O23 - Service: Eset HTTP Server (EhttpSrv) - ESET - C:\Program Files\ESET\ESET NOD32 Antivirus\EHttpSrv.exe
O23 - Service: Eset Service (ekrn) - ESET - C:\Program Files\ESET\ESET NOD32 Antivirus\ekrn.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: eSettings Service (eSettingsService) - Unknown owner - C:\Acer\Empowering Technology\eSettings\Service\capuserv.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: Service de l’iPod (iPod Service) - Apple Inc. - C:\Program Files\iPod\bin\iPodService.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: Raw Socket Service (RS_Service) - Acer Inc. - C:\Program Files\Acer\Acer VCM\RS_Service.exe
O23 - Service: StarWind AE Service (StarWindServiceAE) - Rocket Division Software - C:\Program Files\Alcohol Soft\Alcohol 120\StarWind\StarWindServiceAE.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