il computer dopo essersi connesso a internet mi lascia eseguire solo un paio di ricerce o visualizzare solo un paio di schede e poi mi è impossibile fare qualsiasi cosa..

in pratica si disconnette automaticamente e non mi da la possibilità di rientrare in internet

questo è il log di hijackthis


Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 18.28.02, on 12/11/2009
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16915)
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:\Programmi\AntiVir PersonalEdition Classic\avguard.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\Explorer.EXE
C:\PROGRA~1\Sony\SONICS~1\SsAAD.exe
C:\Programmi\iTunes\iTunesHelper.exe
C:\Programmi\ATI Technologies\ATI.ACE\cli.exe
C:\Programmi\Java\jre6\bin\jusched.exe
C:\Programmi\Messenger\msmsgs.exe
C:\Programmi\AntiVir PersonalEdition Classic\avgnt.exe
C:\Programmi\Windows Live\Messenger\MsnMsgr.Exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Microsoft ActiveSync\wcescomm.exe
C:\PROGRA~1\MICROS~4\rapimgr.exe
C:\Programmi\a-squared Free\a2service.exe
C:\Programmi\AntiVir PersonalEdition Classic\sched.exe
C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\Programmi\Java\jre6\bin\jqs.exe
C:\Programmi\Telecom Italia\WanMiniport1st\srvany.exe
C:\Programmi\Telecom Italia\WanMiniport1st\WanMiniport1st_srv.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Programmi\iPod\bin\iPodService.exe
C:\Programmi\ATI Technologies\ATI.ACE\cli.exe
C:\Programmi\ATI Technologies\ATI.ACE\cli.exe
C:\Programmi\Mozilla Firefox\firefox.exe
C:\Programmi\AntiVir PersonalEdition Classic\update.exe
C:\Programmi\Trend Micro\HijackThis\HijackThis.exe
C:\Programmi\AntiVir PersonalEdition Classic\avwsc.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.yahoo.it/
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 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://windowsupdate.microsoft.com/
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = *.local
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 5.0\Reader\ActiveX\AcroIEHelper.ocx
O2 - BHO: AskBar BHO - {201f27d4-3704-41d6-89c1-aa35e39143ed} - C:\Programmi\AskBarDis\bar\bin\askBar.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Guida per l'accesso a Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Programmi\Java\jre6\bin\jp2ssv.dll
O2 - BHO: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - C:\Programmi\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O3 - Toolbar: Foxit Toolbar - {3041d03e-fd4b-44e0-b742-2d9b88305f98} - C:\Programmi\AskBarDis\bar\bin\askBar.dll
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [SsAAD.exe] C:\PROGRA~1\Sony\SONICS~1\SsAAD.exe
O4 - HKLM\..\Run: [QuickTime Task] "C:\Programmi\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "C:\Programmi\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [ATICCC] "C:\Programmi\ATI Technologies\ATI.ACE\cli.exe" runtime -Delay
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre6\bin\jusched.exe"
O4 - HKCU\..\Run: [MSMSGS] "C:\Programmi\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [avgnt] "C:\Programmi\AntiVir PersonalEdition Classic\avgnt.exe" /min
O4 - HKCU\..\Run: [PinnacleDriverCheck] C:\WINDOWS\system32\\PSDrvCheck.exe
O4 - HKCU\..\Run: [msnmsgr] "C:\Programmi\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [H/PC Connection Agent] "C:\Programmi\Microsoft ActiveSync\wcescomm.exe"
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O9 - Extra button: Create Mobile Favorite - {2EAF5BB1-070F-11D3-9307-00C04FAE2D4F} - C:\PROGRA~1\MICROS~4\INetRepl.dll
O9 - Extra button: (no name) - {2EAF5BB2-070F-11D3-9307-00C04FAE2D4F} - C:\PROGRA~1\MICROS~4\INetRepl.dll
O9 - Extra 'Tools' menuitem: Crea preferiti portatile... - {2EAF5BB2-070F-11D3-9307-00C04FAE2D4F} - C:\PROGRA~1\MICROS~4\INetRepl.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O16 - DPF: Yahoo! Pool 2 - http://download2.games.yahoo.com/games/clients/y/poti_x.cab
O16 - DPF: {20A60F0D-9AFA-4515-A0FD-83BD84642501} (Checkers Class) - http://messenger.zone.msn.com/binary/msgrchkr.cab56986.cab
O16 - DPF: {4F1E5B1A-2A80-42CA-8532-2D05CB959537} (MSN Photo Upload Tool) - http://vangig.spaces.live.com//PhotoUpload/MsnPUpld.cab
O16 - DPF: {5D6F45B3-9043-443D-A792-115447494D24} (UnoCtrl Class) - http://messenger.zone.msn.com/IT-IT/a-UNO1/GAME_UNO1.cab
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://update.microsoft.com/windowsupdate/v6/V5Controls/en/x86/client/wuweb_site.cab?1166160616437
O16 - DPF: {7FC1B346-83E6-4774-8D20-1A6B09B0E737} (Windows Live Photo Upload Control) - http://vangig.spaces.live.com/PhotoUpload/MsnPUpld.cab
O16 - DPF: {8E0D4DE5-3180-4024-A327-4DFAD1796A8D} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsClient.cab31267.cab
O16 - DPF: {B8BE5E93-A60C-4D26-A2DC-220313175592} (MSN Games - Installer) - http://messenger.zone.msn.com/binary/ZIntro.cab56649.cab
O16 - DPF: {C3F79A2B-B9B4-4A66-B012-3EE46475B072} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsPAClient.cab56907.cab
O16 - DPF: {F5A7706B-B9C0-4C89-A715-7A0C6B05DD48} (Minesweeper Flags Class) - http://messenger.zone.msn.com/binary/MineSweeper.cab56986.cab
O23 - Service: a-squared Free Service (a2free) - Emsi Software GmbH - C:\Programmi\a-squared Free\a2service.exe
O23 - Service: AntiVir PersonalEdition Classic Scheduler (AntiVirScheduler) - Avira GmbH - C:\Programmi\AntiVir PersonalEdition Classic\sched.exe
O23 - Service: AntiVir PersonalEdition Classic Guard (AntiVirService) - Avira GmbH - C:\Programmi\AntiVir PersonalEdition Classic\avguard.exe
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
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: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Programmi\File comuni\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: Servizio iPod (iPod Service) - Apple Inc. - C:\Programmi\iPod\bin\iPodService.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Sun Microsystems, Inc. - C:\Programmi\Java\jre6\bin\jqs.exe
O23 - Service: MSCSPTISRV - Sony Corporation - C:\Programmi\File comuni\Sony Shared\AVLib\MSCSPTISRV.exe
O23 - Service: Network WanMiniport First Position - Unknown owner - C:\Programmi\Telecom Italia\WanMiniport1st\srvany.exe
O23 - Service: PACSPTISVR - Sony Corporation - C:\Programmi\File comuni\Sony Shared\AVLib\PACSPTISVR.exe
O23 - Service: Sony SPTI Service (SPTISRV) - Sony Corporation - C:\Programmi\File comuni\Sony Shared\AVLib\SPTISRV.exe
O23 - Service: SonicStage SCSI Service (SSScsiSV) - Sony Corporation - C:\Programmi\File comuni\Sony Shared\AVLib\SSScsiSV.exe

--
End of file - 8803 bytes

Avvia hijackthis, metti la spunta alle voci che andrò ad elencarti e con tutte le applicazioni chiuse e disconnesso da Internet,premi su fix checked
O2 - BHO: AskBar BHO - {201f27d4-3704-41d6-89c1-aa35e39143ed} - C:\Programmi\AskBarDis\bar\bin\askBar.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O3 - Toolbar: Foxit Toolbar - {3041d03e-fd4b-44e0-b742-2d9b88305f98} - C:\Programmi\AskBarDis\bar\bin\askBar.dll
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [QuickTime Task] "C:\Programmi\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "C:\Programmi\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre6\bin\jusched.exe"
O4 - HKCU\..\Run: [MSMSGS] "C:\Programmi\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [msnmsgr] "C:\Programmi\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [H/PC Connection Agent] "C:\Programmi\Microsoft ActiveSync\wcescomm.exe"
TUTTE le 016

Dai una pulita (registro compreso)con CCleaner http://www.aiutaamici.com/software?ID=11223
Nella schermata iniziale di CCleaner, clicca su Opzioni e poi Avanzate, togli il segno di spunta a: Cancella i file in Windows Temp solo se più vecchi di 48 ore. (poi esegui le pulizie)

Riavvia il pc.

Scarica ed installa MalwareBytes:
clicca qui per il download : http://www.aiutamici.com/software?id=80346
Prima di fare la scansione AGGIORNALO. (è molto importante)
Esegui una scansione completa del sistema.
Posta il log.