mi fate un controllo di questo file log di hiJack....
grazie, il pc è un po' rallentato e mi trovo questo nielsen.exe a me sconosciuto....????

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 12.17.46, on 22/12/2010
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
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\system32\spoolsv.exe
C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2009\avp.exe
C:\Programmi\Java\jre6\bin\jqs.exe
C:\Programmi\Microsoft SQL Server\MSSQL\Binn\sqlservr.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\SOUNDMAN.EXE
C:\Programmi\HP\HP Software Update\HPWuSchd2.exe
C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2009\avp.exe
C:\Programmi\File comuni\Real\Update_OB\realsched.exe
C:\Programmi\NetRatingsNetSight\NetSight\NielsenOnline.exe
C:\Programmi\File comuni\Adobe\ARM\1.0\AdobeARM.exe
C:\Programmi\File comuni\Java\Java Update\jusched.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\HP\Digital Imaging\bin\hpqtra08.exe
C:\Programmi\NetRatingsNetSight\NetSight\NielsenOnline.exe
C:\Programmi\Internet Explorer\iexplore.exe
C:\Programmi\HP\Digital Imaging\bin\hpqSTE08.exe
C:\Programmi\Internet Explorer\iexplore.exe
C:\Programmi\File comuni\Java\Java Update\jucheck.exe
C:\WINDOWS\system32\msiexec.exe
C:\Programmi\Trend Micro\HijackThis\HiJackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.libero.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
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: RealPlayer Download and Record Plugin for Internet Explorer - {3049C3E9-B461-4BC5-8870-4C09146192CA} - C:\Documents and Settings\All Users\Dati applicazioni\Real\RealPlayer\BrowserRecordPlugin\IE\rpbrowserrecordplugin.dll
O2 - BHO: IEVkbdBHO - {59273AB4-E7D3-40F9-A1A8-6FA9CCA1862C} - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2009\ievkbd.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - C:\Programmi\Google\Google Toolbar\GoogleToolbar_32.dll (file missing)
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Programmi\Google\GoogleToolbarNotifier\5.6.5805.1910\swg.dll (file missing)
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: Google Toolbar - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - C:\Programmi\Google\Google Toolbar\GoogleToolbar_32.dll (file missing)
O4 - HKLM\..\Run: [SoundMan] SOUNDMAN.EXE
O4 - HKLM\..\Run: [HP Software Update] C:\Programmi\HP\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [AVP] "C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2009\avp.exe"
O4 - HKLM\..\Run: [TkBellExe] "C:\Programmi\File comuni\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [NielsenOnline] C:\Programmi\NetRatingsNetSight\NetSight\NielsenOnline.exe
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Programmi\Adobe\Reader 9.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [Adobe ARM] "C:\Programmi\File comuni\Adobe\ARM\1.0\AdobeARM.exe"
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\File comuni\Java\Java Update\jusched.exe"
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [swg] C:\Programmi\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.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')
O4 - Startup: OpenOffice.org 3.2.lnk = C:\Programmi\OpenOffice.org 3\program\quickstart.exe
O4 - Global Startup: HP Digital Imaging Monitor.lnk = C:\Programmi\HP\Digital Imaging\bin\hpqtra08.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Programmi\Microsoft Office\Office10\OSA.EXE
O8 - Extra context menu item: Aggiungi al banner Blocco pubblicità - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2009\ie_banner_deny.htm
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~3\Office10\EXCEL.EXE/3000
O9 - Extra button: Statistiche sulla protezione del traffico Web - {1F460357-8A94-4D71-9CA3-AA4ACF32ED8E} - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2009\SCIEPlgn.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: {E2883E8F-472F-4FB0-9522-AC9BF37916A7} - http://platformdl.adobe.com/NOS/getPlusPlus/1.6/gp.cab
O20 - AppInit_DLLs: C:\PROGRA~1\KASPER~1\KASPER~1\mzvkbd.dll,C:\PROGRA~1\KASPER~1\KASPER~1\adialhk.dll,C:\PROGRA~1\KASPER~1\KASPER~1\kloehk.dll
O22 - SharedTaskScheduler: Precaricatore Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Daemon di cache delle categorie di componenti - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: Autodesk Licensing Service - Autodesk - C:\Programmi\File comuni\Autodesk Shared\Service\AdskScSrv.exe
O23 - Service: Kaspersky Internet Security (AVP) - Kaspersky Lab - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2009\avp.exe
O23 - Service: Servizio di Google Update (gupdate1ca2d7695473786) (gupdate1ca2d7695473786) - Unknown owner - C:\Programmi\Google\Update\GoogleUpdate.exe (file missing)
O23 - Service: Google Software Updater (gusvc) - Unknown owner - C:\Programmi\Google\Common\Google Updater\GoogleUpdaterService.exe (file missing)
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Programmi\File comuni\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Sun Microsystems, Inc. - C:\Programmi\Java\jre6\bin\jqs.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe

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End of file - 7275 bytes


GRAZIE SERGIO.

A parte quel programma il log è pulito, controlla in istallazioni applicazioni se lo trovi, rimuovilo.
Poi installa Malwarebytes da QUI lo aggiorni e poi
fai una scansione COMPLETA, non veloce, elimina tutto quello che trova, poi fai una pulizia con Ccleaner
compreso il registro, poi vai in c:\windows e cerca la cartella Prefetch aprila ed elimina tutto il contenuto, non eliminare la cartella.
Rifai una scansione con HJT e posta il nuovo log.