Impossible d'installer un antivirus

Bonjour tout le monde;
j'ai 3 PC en réseau mes problèmes sont :
-Pas d'accès à la base de registre
-Pas d'accès au gestionnaires des tâches
-Installation d'un antivirus est impossible
Voilà les rapports de HijackThis

-Poste1
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 14:22:15, on 27/10/2011
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
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\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Java\j2re1.4.2_05\bin\jusched.exe
C:\Program Files\Hewlett-Packard\Toolbox2.0\Apache Tomcat 4.0\webapps\Toolbox\StatusClient\StatusClient.exe
C:\Program Files\Lexmark 7300 Series\lxcimon.exe
C:\Program Files\Lexmark 7300 Series\ezprint.exe
C:\Program Files\Modem Samsung SCH-U209\sysctrlU.exe
C:\Program Files\Modem Samsung SCH-U209\SamsungPnPServiceManager.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\lxcicoms.exe
G:\HiJackThis.exe

R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: (no name) - {FFFFFEF0-5B30-21D4-945D-000000000000} - C:\PROGRA~1\STARDO~1\SDIEInt.dll
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\system32\msdxm.ocx
O3 - Toolbar: Star Downloader Toolbar - {8CEB3591-5DDC-47ec-AF97-66699BC85FE0} - C:\Program Files\Star Downloader Toolbar\v2.0.0.5\Star_Downloader_Toolbar.dll
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINDOWS\system32\NeroCheck.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] C:\Program Files\Java\j2re1.4.2_05\bin\jusched.exe
O4 - HKLM\..\Run: [StatusClient] C:\Program Files\Hewlett-Packard\Toolbox2.0\Apache Tomcat 4.0\webapps\Toolbox\StatusClient\StatusClient.exe /auto
O4 - HKLM\..\Run: [TomcatStartup] C:\Program Files\Hewlett-Packard\Toolbox2.0\hpbpsttp.exe
O4 - HKLM\..\Run: [LXCICATS] rundll32 C:\WINDOWS\System32\spool\DRIVERS\W32X86\3\LXCItime.dll,_RunDLLEntry@16
O4 - HKLM\..\Run: [lxcimon.exe] "C:\Program Files\Lexmark 7300 Series\lxcimon.exe"
O4 - HKLM\..\Run: [EzPrint] "C:\Program Files\Lexmark 7300 Series\ezprint.exe"
O4 - HKCU\..\Run: [Z810SysStart] C:\Program Files\Modem Samsung SCH-U209\sysctrlU.exe
O4 - HKCU\..\Run: [Z810PNP] C:\Program Files\Modem Samsung SCH-U209\SamsungPnPServiceManager.exe
O7 - HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System, DisableRegedit=1
O8 - Extra context menu item: Download with Star Downloader - C:\Program Files\Star Downloader\sdie.htm
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\Microsoft Office\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\j2re1.4.2_05\bin\npjpi142_05.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\j2re1.4.2_05\bin\npjpi142_05.dll
O23 - Service: hdlSrv - Unknown owner - C:\Program Files\M-Systems Utility\hdlSrv.exe
O23 - Service: lxci_device - - C:\WINDOWS\system32\lxcicoms.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe

--
End of file - 3434 bytes

-Poste2
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 22:19:05, on 27/10/2011
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\arservice.exe
C:\WINDOWS\eHome\ehRecvr.exe
C:\WINDOWS\eHome\ehSched.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\Program Files\PC SOFT\Serveur HyperFileSQL\Manta.exe
C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
C:\Program Files\PC SOFT\Serveur HyperFileSQL\MantaManager.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Fichiers communs\AVG Secure Search\vToolbarUpdater\8.0.1\ToolbarUpdater.exe
C:\WINDOWS\system32\wuauclt.exe
C:\WINDOWS\ehome\ehtray.exe
C:\WINDOWS\ARPWRMSG.EXE
C:\Program Files\Java\jre1.5.0\bin\jusched.exe
C:\windows\system\hpsysdrv.exe
C:\Program Files\ATI Technologies\ATI.ACE\cli.exe
C:\WINDOWS\SOUNDMAN.EXE
C:\WINDOWS\ALCWZRD.EXE
C:\HP\KBD\KBD.EXE
C:\Program Files\iTunes\iTunesHelper.exe
C:\hp\drivers\hplsbwatcher\lsburnwatcher.exe
C:\Program Files\HP\HP Software Update\HPwuSchd2.exe
C:\Program Files\KodakDigitalImagingTransfer\KDIT.exe
C:\Program Files\AVG Secure Search\vprot.exe
C:\Program Files\Modem Samsung SCH-U209\SamsungPnPServiceManager.exe
C:\WINDOWS\system32\dllhost.exe
C:\Program Files\Modem Samsung SCH-U209\sysctrlU.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\Program Files\HP\Digital Imaging\bin\hpqtra08.exe
C:\WINDOWS\eHome\ehmsas.exe
C:\TW2\VDDSSvr.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Program Files\DentiSoft\DentiSoft.exe
C:\WINDOWS\msagent\AgentSvr.exe
K:\HiJackThis.exe

R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://www.wana.ma/
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: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Program Files\AVG\AVG2012\avgssie.dll (file missing)
O2 - BHO: AVG Security Toolbar - {95B7759C-8C7F-4BF1-B163-73684A933233} - C:\Program Files\AVG Secure Search\8.0.0.34\AVG Secure Search_toolbar.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar1.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar1.dll
O3 - Toolbar: AVG Security Toolbar - {95B7759C-8C7F-4BF1-B163-73684A933233} - C:\Program Files\AVG Secure Search\8.0.0.34\AVG Secure Search_toolbar.dll
O4 - HKLM\..\Run: [ehTray] C:\WINDOWS\ehome\ehtray.exe
O4 - HKLM\..\Run: [AlwaysReady Power Message APP] ARPWRMSG.EXE
O4 - HKLM\..\Run: [SunJavaUpdateSched] C:\Program Files\Java\jre1.5.0\bin\jusched.exe
O4 - HKLM\..\Run: [hpsysdrv] c:\windows\system\hpsysdrv.exe
O4 - HKLM\..\Run: [Raccourci vers la page des propriétés de High Definition Audio] HDAShCut.exe
O4 - HKLM\..\Run: [ATICCC] "C:\Program Files\ATI Technologies\ATI.ACE\cli.exe" runtime
O4 - HKLM\..\Run: [SoundMan] SOUNDMAN.EXE
O4 - HKLM\..\Run: [AlcWzrd] ALCWZRD.EXE
O4 - HKLM\..\Run: [HPHUPD08] c:\Program Files\HP\Digital Imaging\{33D6CC28-9F75-4d1b-A11D-98895B3A3729}\hphupd08.exe
O4 - HKLM\..\Run: [KBD] C:\HP\KBD\KBD.EXE
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [Recguard] C:\WINDOWS\SMINST\RECGUARD.EXE
O4 - HKLM\..\Run: [PS2] C:\WINDOWS\system32\ps2.exe
O4 - HKLM\..\Run: [LSBWatcher] c:\hp\drivers\hplsbwatcher\lsburnwatcher.exe
O4 - HKLM\..\Run: [Reminder] "C:\Windows\Creator\Remind_XP.exe"
O4 - HKLM\..\Run: [HP Software Update] C:\Program Files\HP\HP Software Update\HPwuSchd2.exe
O4 - HKLM\..\Run: [KDIT] C:\Program Files\KodakDigitalImagingTransfer\KDIT.exe
O4 - HKLM\..\Run: [vProt] "C:\Program Files\AVG Secure Search\vprot.exe"
O4 - HKCU\..\Run: [Z810PNP] C:\Program Files\Modem Samsung SCH-U209\SamsungPnPServiceManager.exe
O4 - HKCU\..\Run: [Z810SysStart] C:\Program Files\Modem Samsung SCH-U209\sysctrlU.exe
O4 - Global Startup: Barre d'état système d'ATI CATALYST.lnk = C:\Program Files\ATI Technologies\ATI.ACE\CLI.exe
O4 - Global Startup: HP Digital Imaging Monitor.lnk = C:\Program Files\HP\Digital Imaging\bin\hpqtra08.exe
O4 - Global Startup: Lancer le serveur VDDS.lnk = C:\TW2\VDDSSvr.exe
O7 - HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System, DisableRegedit=1
O8 - Extra context menu item: &Google Search - res://C:\Program Files\Google\GoogleToolbar1.dll/cmsearch.html
O8 - Extra context menu item: Pages liées - res://C:\Program Files\Google\GoogleToolbar1.dll/cmbacklinks.html
O8 - Extra context menu item: Pages similaires - res://C:\Program Files\Google\GoogleToolbar1.dll/cmsimilar.html
O8 - Extra context menu item: Version de la page actuelle disponible dans le cache Google - res://C:\Program Files\Google\GoogleToolbar1.dll/cmcache.html
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0\bin\npjpi150.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0\bin\npjpi150.dll
O9 - Extra button: Aide à la connexion - {E2D4D26B-0180-43a4-B05F-462D6D54C789} - C:\WINDOWS\PCHEALTH\HELPCTR\Vendors\CN=Hewlett-Packard,L=Cupertino,S=Ca,C=US\IEButton\support.htm
O9 - Extra 'Tools' menuitem: Aide à la connexion - {E2D4D26B-0180-43a4-B05F-462D6D54C789} - C:\WINDOWS\PCHEALTH\HELPCTR\Vendors\CN=Hewlett-Packard,L=Cupertino,S=Ca,C=US\IEButton\support.htm
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
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Program Files\AVG\AVG2012\avgpp.dll (file missing)
O18 - Protocol: viprotocol - {B658800C-F66E-4EF3-AB85-6C0C227862A9} - C:\Program Files\Fichiers communs\AVG Secure Search\ViProtocolInstaller\8.0.1\ViProtocol.dll
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: AVGIDSAgent - Unknown owner - C:\Program Files\AVG\AVG2012\AVGIDSAgent.exe (file missing)
O23 - Service: Hyper File Server : reda - PC SOFT - C:\Program Files\PC SOFT\Serveur HyperFileSQL\Manta.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: iPod Service (iPodService) - Apple Computer, Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
O23 - Service: MantaManager - PC SOFT - C:\Program Files\PC SOFT\Serveur HyperFileSQL\MantaManager.exe
O23 - Service: vToolbarUpdater - Unknown owner - C:\Program Files\Fichiers communs\AVG Secure Search\vToolbarUpdater\8.0.1\ToolbarUpdater.exe

--
End of file - 7715 bytes

-Poste3

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 20:15, on 27/10/2011
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
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\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\hkcmd.exe
C:\WINDOWS\system32\igfxpers.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\SuperCopier2\SuperCopier2.exe
C:\Program Files\Messenger\msmsgs.exe
C:\Program Files\Modem Samsung SCH-U209\sysctrlU.exe
C:\Program Files\Modem Samsung SCH-U209\SamsungPnPServiceManager.exe
C:\Program Files\Fichiers communs\Microsoft Shared\VS7DEBUG\MDM.EXE
F:\HiJackThis.exe
C:\WINDOWS\system32\wbem\wmiprvse.exe

R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O4 - HKLM\..\Run: [igfxtray] C:\WINDOWS\system32\igfxtray.exe
O4 - HKLM\..\Run: [igfxhkcmd] C:\WINDOWS\system32\hkcmd.exe
O4 - HKLM\..\Run: [igfxpers] C:\WINDOWS\system32\igfxpers.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [SuperCopier2.exe] C:\Program Files\SuperCopier2\SuperCopier2.exe
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [Z810SysStart] C:\Program Files\Modem Samsung SCH-U209\sysctrlU.exe
O4 - HKCU\..\Run: [Z810PNP] C:\Program Files\Modem Samsung SCH-U209\SamsungPnPServiceManager.exe
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [nlsf] cmd.exe /C move /Y "%SystemRoot%\System32\syssetub.dll" "%SystemRoot%\System32\syssetup.dll" (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [nlsf] cmd.exe /C move /Y "%SystemRoot%\System32\syssetub.dll" "%SystemRoot%\System32\syssetup.dll" (User 'Default user')
O7 - HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System, DisableRegedit=1
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~1\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Recherche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~1\OFFICE11\REFIEBAR.DLL
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
O10 - Unknown file in Winsock LSP: c:\windows\system32\nwprovau.dll

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End of file - 3240 bytes
Merci inifiniment,