Allego il log di hijackthis:
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 17.40.43, on 29/08/2012
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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\Avira\AntiVir Desktop\sched.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\Avira\AntiVir Desktop\avgnt.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\ATI Technologies\ATI.ACE\Core-Static\MOM.exe
C:\Programmi\ATI Technologies\ATI.ACE\Core-Static\ccc.exe
C:\Programmi\Avira\AntiVir Desktop\avguard.exe
C:\Programmi\NVIDIA Corporation\NetworkAccessManager\bin32\nSvcAppFlt.exe
C:\Programmi\Java\jre7\bin\jqs.exe
C:\Programmi\Nero\Update\NASvc.exe
C:\Programmi\CDBurnerXP\NMSAccessU.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\NVIDIA Corporation\NetworkAccessManager\bin32\nSvcIp.exe
C:\Programmi\Avira\AntiVir Desktop\avshadow.exe
C:\Programmi\Internet Explorer\IEXPLORE.EXE
C:\Documents and Settings\All Users\Documenti\AppData\PoApp\PService.exe
C:\Programmi\Internet Explorer\IEXPLORE.EXE
C:\Programmi\Malwarebytes' Anti-Malware\mbam.exe
C:\Programmi\Internet Explorer\IEXPLORE.EXE
C:\Programmi\Internet Explorer\IEXPLORE.EXE
C:\Documents and Settings\Pomata\Desktop\Nuova cartella\HiJackThis PORTABLE.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.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://www.bigseekpro.com/splitcam/{35C1120C-1C5E-470D-9FB3-5953A20202CC}
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: Groove GFS Browser Helper - {72853161-30C5-4D22-B7F9-0BBC1D38A37E} - C:\PROGRA~1\Microsoft Office\Office14\GROOVEEX.DLL
O2 - BHO: SearchToolbar.ShowToolbarBHO - {86a3cdaa-9b25-480e-b73f-c2d359b87966} - mscoree.dll (file missing)
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: URLRedirectionBHO - {B4F3A835-0E21-4959-BA22-42B3008E02FF} - C:\PROGRA~1\Microsoft Office\Office14\URLREDIR.DLL
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Programmi\Java\jre7\bin\jp2ssv.dll
O3 - Toolbar: SearchToolbar - {691ca8ec-7205-4aa9-bdd6-15493d16f835} - mscoree.dll (file missing)
O4 - HKLM\..\Run: [StartCCC] "C:\Programmi\ATI Technologies\ATI.ACE\Core-Static\CLIStart.exe" MSRun
O4 - HKLM\..\Run: [avgnt] "C:\Programmi\Avira\AntiVir Desktop\avgnt.exe" /min
O4 - HKLM\..\Run: [PosService] C:\Documents and Settings\All Users\Documenti\AppData\PoApp\PLauncher.exe
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-20\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'Default user')
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\Microsoft Office\Office14\EXCEL.EXE/3000
O8 - Extra context menu item: I&nvia a OneNote - res://C:\PROGRA~1\Microsoft Office\Office14\ONBttnIE.dll/105
O9 - Extra button: Invia a OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\Programmi\Microsoft Office\Office14\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: I&nvia a OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\Programmi\Microsoft Office\Office14\ONBttnIE.dll
O9 - Extra button: &Note collegate di OneNote - {789FE86F-6FC4-46A1-9849-EDE0DB0C95CA} - C:\Programmi\Microsoft Office\Office14\ONBttnIELinkedNotes.dll
O9 - Extra 'Tools' menuitem: &Note collegate di OneNote - {789FE86F-6FC4-46A1-9849-EDE0DB0C95CA} - C:\Programmi\Microsoft Office\Office14\ONBttnIELinkedNotes.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
O10 - Unknown file in Winsock LSP: c:\programmi\nvidia corporation\networkaccessmanager\bin32\nvlsp.dll
O10 - Unknown file in Winsock LSP: c:\programmi\nvidia corporation\networkaccessmanager\bin32\nvlsp.dll
O10 - Unknown file in Winsock LSP: c:\programmi\nvidia corporation\networkaccessmanager\bin32\nvlsp.dll
O10 - Unknown file in Winsock LSP: c:\programmi\nvidia corporation\networkaccessmanager\bin32\nvlsp.dll
O13 - Gopher Prefix:
O16 - DPF: {9122D757-5A4F-4768-82C5-B4171D8556A7} (PhotoPickConvert Class) - http://appdirectory.messenger.msn.com/AppDirectory/P4Apps/PhotoSwap/PhtPkMSN.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{1D291992-8A88-42F1-A815-6FAF681FB211}: NameServer = 176.31.229.24,176.31.229.25
O17 - HKLM\System\CCS\Services\Tcpip\..\{34AB5661-3CF1-4F98-B42E-F1C9944F860F}: NameServer = 176.31.229.24,176.31.229.25
O17 - HKLM\System\CCS\Services\Tcpip\..\{53518E38-9158-45E5-8632-3E52AB7599C6}: NameServer = 176.31.229.24,176.31.229.25
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\Skype4COM.dll
O18 - Filter hijack: text/xml - {807573E5-5146-11D5-A672-00B0D022E945} - C:\Programmi\File comuni\Microsoft Shared\OFFICE14\MSOXMLMF.DLL
O23 - Service: Avira Pianificatore (AntiVirSchedulerService) - Avira Operations GmbH & Co. KG - C:\Programmi\Avira\AntiVir Desktop\sched.exe
O23 - Service: Avira Realtime Protection (AntiVirService) - Avira Operations GmbH & Co. KG - C:\Programmi\Avira\AntiVir Desktop\avguard.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: ForceWare Intelligent Application Manager (IAM) - Unknown owner - C:\Programmi\NVIDIA Corporation\NetworkAccessManager\bin32\nSvcAppFlt.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Oracle Corporation - C:\Programmi\Java\jre7\bin\jqs.exe
O23 - Service: Nero Update (NAUpdate) - Nero AG - C:\Programmi\Nero\Update\NASvc.exe
O23 - Service: NMSAccess - Unknown owner - C:\Programmi\CDBurnerXP\NMSAccessU.exe
O23 - Service: ForceWare IP service (nSvcIp) - Unknown owner - C:\Programmi\NVIDIA Corporation\NetworkAccessManager\bin32\nSvcIp.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Pos Service (PowerOffer Service) - PowerOfferService - C:\Documents and Settings\Pomata\Impostazioni locali\Dati applicazioni\PosService\Pos.exe
O23 - Service: Serv Updater (ServUpdater) - ServiceUpd - C:\Documents and Settings\Pomata\Impostazioni locali\Dati applicazioni\ServUpdater\ServiceUpd.exe
O23 - Service: Skype Updater (SkypeUpdate) - Skype Technologies - C:\Programmi\Skype\Updater\Updater.exe
O23 - Service: Software Upd (SoftwareUpd) - SoftwareUpdService - C:\Documents and Settings\Pomata\Impostazioni locali\Dati applicazioni\SoftwareUpdater\SoftwareUpdService.exe

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