Salve.s.o. windows 7 home premium a 64 bit,sto' impazzendo,scansiono con tutto cio' che è possibile nessun virus o trojan,tutto funziona bene,appena installo un antivirus nel pc portatile acer aspire 5732zg,nel momento in cui riaccendo il pc windows non parte mi fà fare obbligatoriamente il ripristino pc per andare e al riavvio ovviamente l'antivirus è sparito,ho provato sia ad installare avg che avast fà la stessa cosa!!!
post log vedete se riuscite a vedere qualcosa da qui..grazie.

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 18:33:59, on 31/03/2012
Platform: Windows 7 SP1 (WinNT 6.00.3505)
MSIE: Internet Explorer v9.00 (9.00.8112.16421)
Boot mode: Normal

Running processes:
C:\Program Files (x86)\Intel\Intel Matrix Storage Manager\IAAnotif.exe
C:\Windows\PLFSetI.exe
C:\Program Files (x86)\Nokia\Nokia PC Suite 6\PcSync2.exe
C:\Program Files (x86)\DAEMON Tools Lite\DTLite.exe
C:\Windows\System\w98eject.exe
C:\Program Files (x86)\OpenOffice.org 3\program\soffice.exe
C:\Program Files (x86)\OpenOffice.org 3\program\soffice.bin
C:\Program Files (x86)\Common Files\Nokia\MPAPI\MPAPI3s.exe
C:\Program Files (x86)\Launch Manager\LManager.exe
C:\Program Files (x86)\Acer Arcade Deluxe\Acer Arcade Deluxe\ArcadeDeluxeAgent.exe
C:\Program Files (x86)\Acer Arcade Deluxe\PlayMovie\PMVService.exe
C:\Program Files (x86)\Nokia\Nokia PC Suite 6\LaunchApplication.exe
C:\Program Files (x86)\Common Files\Java\Java Update\jusched.exe
C:\Program Files (x86)\Trend Micro\HiJackThis\HiJackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://homepage.acer.com/rdr.aspx?b=ACAW&l=0410&m=aspire_5732z&r=27360510l915l04h4z195t4552c746
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://homepage.acer.com/rdr.aspx?b=ACAW&l=0410&m=aspire_5732z&r=27360510l915l04h4z195t4552c746
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 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://homepage.acer.com/rdr.aspx?b=ACAW&l=0410&m=aspire_5732z&r=27360510l915l04h4z195t4552c746
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Local Page = C:\Windows\SysWOW64\blank.htm
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = 127.0.0.1:9421
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
R3 - URLSearchHook: (no name) - {F3FEE66E-E034-436a-86E4-9690573BEE8A} - (no file)
R3 - URLSearchHook: (no name) - {e3393495-8103-46a0-8181-270273eddd60} - (no file)
R3 - URLSearchHook: (no name) - {4ae0c3d6-f713-4eed-bc65-25dc3ffdaac1} - (no file)
R3 - URLSearchHook: (no name) - {a1e75a0e-4397-4ba8-bb50-e19fb66890f4} - (no file)
F2 - REG:system.ini: UserInit=userinit.exe
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files (x86)\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Program Files (x86)\AVG\AVG10\avgssie.dll (file missing)
O2 - BHO: Java(tm) Plug-In SSV Helper - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files (x86)\Java\jre6\bin\ssv.dll
O2 - BHO: Guida per l'accesso a Windows Live ID - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files (x86)\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Windows Live Messenger Companion Helper - {9FDDE16B-836F-4806-AB1F-1455CBEFF289} - C:\Program Files (x86)\Windows Live\Companion\companioncore.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files (x86)\Java\jre6\bin\jp2ssv.dll
O4 - HKLM\..\Run: [LManager] C:\Program Files (x86)\Launch Manager\LManager.exe
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files (x86)\Adobe\Reader 9.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [ArcadeDeluxeAgent] "C:\Program Files (x86)\Acer Arcade Deluxe\Acer Arcade Deluxe\ArcadeDeluxeAgent.exe"
O4 - HKLM\..\Run: [PlayMovie] "C:\Program Files (x86)\Acer Arcade Deluxe\PlayMovie\PMVService.exe"
O4 - HKLM\..\Run: [StartCCC] "C:\Program Files (x86)\ATI Technologies\ATI.ACE\Core-Static\CLIStart.exe" MSRun
O4 - HKLM\..\Run: [NeroFilterCheck] C:\Windows\SysWOW64\NeroCheck.exe
O4 - HKLM\..\Run: [PCSuiteTrayApplication] C:\PROGRA~2\Nokia\NOKIAP~1\LAUNCH~1.EXE -startup
O4 - HKLM\..\Run: [AVG_TRAY] C:\Program Files (x86)\AVG\AVG10\avgtray.exe
O4 - HKLM\..\Run: [NeroCheck] C:\Windows\system32\NeroCheck.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files (x86)\Common Files\Java\Java Update\jusched.exe"
O4 - HKCU\..\Run: [PcSync] C:\Program Files (x86)\Nokia\Nokia PC Suite 6\PcSync2.exe /NoDialog
O4 - HKCU\..\Run: [DAEMON Tools Lite] "C:\Program Files (x86)\DAEMON Tools Lite\DTLite.exe" -autorun
O4 - HKCU\..\Run: [EA Core] "C:\Program Files (x86)\Electronic Arts\EADM\Core.exe" -silent
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /autoRun (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\RunOnce: [mctadmin] C:\Windows\System32\mctadmin.exe (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /autoRun (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-20\..\RunOnce: [mctadmin] C:\Windows\System32\mctadmin.exe (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-18\..\Run: [AMService] C:\Windows\TEMP\texllc\setup.exe (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [AMService] C:\Windows\TEMP\texllc\setup.exe (User 'Default user')
O4 - Startup: OpenOffice.org 3.2.lnk = C:\Program Files (x86)\OpenOffice.org 3\program\quickstart.exe
O4 - Global Startup: w98Eject.lnk = ?
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~2\MICROS~1\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: Google Sidewiki... - res://C:\Program Files (x86)\Google\Google Toolbar\Component\GoogleToolbarDynamic_mui_en_D183CA64F05FDD98.dll/cmsidewiki.html
O9 - Extra button: @C:\Program Files (x86)\Windows Live\Companion\companionlang.dll,-600 - {0000036B-C524-4050-81A0-243669A86B9F} - C:\Program Files (x86)\Windows Live\Companion\companioncore.dll
O9 - Extra button: @C:\Program Files (x86)\Windows Live\Writer\WindowsLiveWriterShortcuts.dll,-1004 - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files (x86)\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra 'Tools' menuitem: @C:\Program Files (x86)\Windows Live\Writer\WindowsLiveWriterShortcuts.dll,-1003 - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files (x86)\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra button: Send to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~2\MICROS~1\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: S&end to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~2\MICROS~1\Office12\ONBttnIE.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~2\MICROS~1\Office12\REFIEBAR.DLL
O10 - Unknown file in Winsock LSP: c:\program files (x86)\common files\microsoft shared\windows live\wlidnsp.dll
O10 - Unknown file in Winsock LSP: c:\program files (x86)\common files\microsoft shared\windows live\wlidnsp.dll
O11 - Options group: [ACCELERATED_GRAPHICS] Accelerated graphics
O16 - DPF: {5D6F45B3-9043-443D-A792-115447494D24} (UnoCtrl Class) - http://messenger.zone.msn.com/MessengerGamesContent/GameContent/it/uno1/GAME_UNO1.cab
O16 - DPF: {C345E174-3E87-4F41-A01C-B066A90A49B4} (WRC Class) - http://trial.trymicrosoftoffice.com/trialoaa/buymsoffice_assets/framework/microsoft/wrc32.ocx
O16 - DPF: {C3F79A2B-B9B4-4A66-B012-3EE46475B072} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsPAClient.cab56907.cab
O16 - DPF: {E2883E8F-472F-4FB0-9522-AC9BF37916A7} - http://platformdl.adobe.com/NOS/getPlusPlus/1.6/gp.cab
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Program Files (x86)\AVG\AVG10\avgpp.dll (file missing)
O18 - Protocol: wlpg - {E43EF6CD-A37A-4A9B-9E6F-83F89B8E6324} - C:\Program Files (x86)\Windows Live\Photo Gallery\AlbumDownloadProtocolHandler.dll
O23 - Service: Adobe Flash Player Update Service (AdobeFlashPlayerUpdateSvc) - Adobe Systems Incorporated - C:\Windows\SysWOW64\Macromed\Flash\FlashPlayerUpdateService.exe
O23 - Service: @%SystemRoot%\system32\Alg.exe,-112 (ALG) - Unknown owner - C:\Windows\System32\alg.exe (file missing)
O23 - Service: AMD External Events Utility - Unknown owner - C:\Windows\system32\atiesrxx.exe (file missing)
O23 - Service: AVG Firewall (avgfws) - Unknown owner - C:\Program Files (x86)\AVG\AVG10\avgfws.exe (file missing)
O23 - Service: AVGIDSAgent - Unknown owner - C:\Program Files (x86)\AVG\AVG10\Identity Protection\Agent\Bin\AVGIDSAgent.exe (file missing)
O23 - Service: AVG WatchDog (avgwd) - Unknown owner - C:\Program Files (x86)\AVG\AVG10\avgwdsvc.exe (file missing)
O23 - Service: @%SystemRoot%\system32\efssvc.dll,-100 (EFS) - Unknown owner - C:\Windows\System32\lsass.exe (file missing)
O23 - Service: Acer ePower Service (ePowerSvc) - Acer Incorporated - C:\Program Files\Acer\Acer ePower Management\ePowerSvc.exe
O23 - Service: @%systemroot%\system32\fxsresm.dll,-118 (Fax) - Unknown owner - C:\Windows\system32\fxssvc.exe (file missing)
O23 - Service: GRegService (Greg_Service) - Acer Incorporated - C:\Program Files (x86)\Acer\Registration\GregHSRW.exe
O23 - Service: Intel(R) Matrix Storage Event Monitor (IAANTMON) - Intel Corporation - C:\Program Files (x86)\Intel\Intel Matrix Storage Manager\IAANTMon.exe
O23 - Service: @keyiso.dll,-100 (KeyIso) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: @comres.dll,-2797 (MSDTC) - Unknown owner - C:\Windows\System32\msdtc.exe (file missing)
O23 - Service: @%SystemRoot%\System32\netlogon.dll,-102 (Netlogon) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: NTI Backup Now 5 Backup Service (NTIBackupSvc) - NewTech InfoSystems, Inc. - C:\Program Files (x86)\NewTech Infosystems\NTI Backup Now 5\BackupSvc.exe
O23 - Service: NTI Backup Now 5 Scheduler Service (NTISchedulerSvc) - NewTech Infosystems, Inc. - C:\Program Files (x86)\NewTech Infosystems\NTI Backup Now 5\SchedulerSvc.exe
O23 - Service: @%systemroot%\system32\psbase.dll,-300 (ProtectedStorage) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: @%systemroot%\system32\Locator.exe,-2 (RpcLocator) - Unknown owner - C:\Windows\system32\locator.exe (file missing)
O23 - Service: @%SystemRoot%\system32\samsrv.dll,-1 (SamSs) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: ServiceLayer - Nokia. - C:\Program Files (x86)\Common Files\PCSuite\Services\ServiceLayer.exe
O23 - Service: @%SystemRoot%\system32\snmptrap.exe,-3 (SNMPTRAP) - Unknown owner - C:\Windows\System32\snmptrap.exe (file missing)
O23 - Service: @%systemroot%\system32\spoolsv.exe,-1 (Spooler) - Unknown owner - C:\Windows\System32\spoolsv.exe (file missing)
O23 - Service: @%SystemRoot%\system32\sppsvc.exe,-101 (sppsvc) - Unknown owner - C:\Windows\system32\sppsvc.exe (file missing)
O23 - Service: @%SystemRoot%\system32\ui0detect.exe,-101 (UI0Detect) - Unknown owner - C:\Windows\system32\UI0Detect.exe (file missing)
O23 - Service: Updater Service - Acer - C:\Program Files\Acer\Acer Updater\UpdaterService.exe
O23 - Service: @%SystemRoot%\system32\vaultsvc.dll,-1003 (VaultSvc) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: @%SystemRoot%\system32\vds.exe,-100 (vds) - Unknown owner - C:\Windows\System32\vds.exe (file missing)
O23 - Service: @%systemroot%\system32\vssvc.exe,-102 (VSS) - Unknown owner - C:\Windows\system32\vssvc.exe (file missing)
O23 - Service: @%SystemRoot%\system32\Wat\WatUX.exe,-601 (WatAdminSvc) - Unknown owner - C:\Windows\system32\Wat\WatAdminSvc.exe (file missing)
O23 - Service: @%systemroot%\system32\wbengine.exe,-104 (wbengine) - Unknown owner - C:\Windows\system32\wbengine.exe (file missing)
O23 - Service: @%Systemroot%\system32\wbem\wmiapsrv.exe,-110 (wmiApSrv) - Unknown owner - C:\Windows\system32\wbem\WmiApSrv.exe (file missing)
O23 - Service: @%PROGRAMFILES%\Windows Media Player\wmpnetwk.exe,-101 (WMPNetworkSvc) - Unknown owner - C:\Program Files (x86)\Windows Media Player\wmpnetwk.exe (file missing)

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End of file - 12342 bytes

Metti il log nella sezione Sicurezza virus.