Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 23:31:03, on 12/02/2011
Platform: Windows 7 (WinNT 6.00.3504)
MSIE: Internet Explorer v9.00 (9.00.7930.16406)
Boot mode: Normal

Running processes:
C:\Program Files (x86)\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Program Files (x86)\Skype\Phone\Skype.exe
C:\Program Files (x86)\Internet Explorer\IELowutil.exe
C:\Program Files (x86)\PokerStars.IT\PokerStars.exe
C:\Users\christian\AppData\Local\Google\Chrome\Application\chrome.exe
C:\Users\christian\AppData\Local\Google\Chrome\Application\chrome.exe
C:\Users\christian\AppData\Local\Google\Chrome\Application\chrome.exe
C:\Users\christian\AppData\Local\Google\Chrome\Application\chrome.exe
C:\Program Files (x86)\Internet Explorer\iexplore.exe
C:\Program Files (x86)\Internet Explorer\iexplore.exe
C:\Program Files (x86)\Google\Google Toolbar\GoogleToolbarUser_32.exe
C:\Windows\SysWOW64\Macromed\Flash\FlashUtil10l_ActiveX.exe
C:\Program Files (x86)\Trend Micro\HiJackThis\HiJackThis.exe
C:\Program Files (x86)\Internet Explorer\iexplore.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = Preserve
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://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 - 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
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
F2 - REG:system.ini: UserInit=userinit.exe
O2 - BHO: HP Print Enhancer - {0347C33E-8762-4905-BF09-768834316C61} - C:\Program Files (x86)\HP\Digital Imaging\Smart Web Printing\hpswp_printenhancer.dll
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files (x86)\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.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: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - C:\Program Files (x86)\Google\Google Toolbar\GoogleToolbar_32.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files (x86)\Java\jre6\bin\jp2ssv.dll
O2 - BHO: HP Smart BHO Class - {FFFFFFFF-CF4E-4F2B-BDC2-0E72E116A856} - C:\Program Files (x86)\HP\Digital Imaging\Smart Web Printing\hpswp_BHO.dll
O3 - Toolbar: Google Toolbar - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - C:\Program Files (x86)\Google\Google Toolbar\GoogleToolbar_32.dll
O4 - HKLM\..\Run: [Adobe ARM] "C:\Program Files (x86)\Common Files\Adobe\ARM\1.0\AdobeARM.exe"
O4 - HKCU\..\Run: [swg] "C:\Program Files (x86)\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe"
O4 - HKCU\..\Run: [Skype] "C:\Program Files (x86)\Skype\Phone\Skype.exe" /nosplash /minimized
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [Google Update] "C:\Users\christian\AppData\Local\Google\Update\GoogleUpdate.exe" /c
O4 - HKCU\..\RunOnce: [FlashPlayerUpdate] C:\Windows\SysWOW64\Macromed\Flash\FlashUtil10l_ActiveX.exe -update activex
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')
O8 - Extra context menu item: Google Sidewiki... - res://C:\Program Files (x86)\Google\Google Toolbar\Component\GoogleToolbarDynamic_mui_en_E11712C84EA7E12B.dll/cmsidewiki.html
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~2\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: PokerStars.it - {C4046502-6524-4d87-896C-878F57D1FF07} - C:\Program Files (x86)\PokerStars.IT\PokerStarsUpdate.exe
O9 - Extra button: Visualizza o nasconde HP Smart Web Printing - {DDE87865-83C5-48c4-8357-2F5B1AA84522} - C:\Program Files (x86)\HP\Digital Imaging\Smart Web Printing\hpswp_BHO.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: {0D41B8C5-2599-4893-8183-00195EC8D5F9} - http://support.asus.com/common/asusTek_sys_ctrl.cab
O16 - DPF: {1E54D648-B804-468d-BC78-4AFFED8E262F} (System Requirements Lab) - http://www.nvidia.com/content/DriverDownload/srl/3.0.0.4/srl_bin/sysreqlab_nvd.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - https://fpdownload.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O16 - DPF: {E2883E8F-472F-4FB0-9522-AC9BF37916A7} - http://platformdl.adobe.com/NOS/getPlusPlus/1.6/gp.cab
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~2\COMMON~1\Skype\SKYPE4~1.DLL
O18 - Protocol: wlpg - {E43EF6CD-A37A-4A9B-9E6F-83F89B8E6324} - C:\Program Files (x86)\Windows Live\Photo Gallery\AlbumDownloadProtocolHandler.dll
O20 - AppInit_DLLs: C:\Windows\SysWOW64\guard32.dll
O23 - Service: @%SystemRoot%\system32\Alg.exe,-112 (ALG) - Unknown owner - C:\Windows\System32\alg.exe (file missing)
O23 - Service: COMODO Internet Security Helper Service (cmdAgent) - COMODO - C:\Program Files\COMODO\COMODO Internet Security\cmdagent.exe
O23 - Service: @%SystemRoot%\system32\efssvc.dll,-100 (EFS) - Unknown owner - C:\Windows\System32\lsass.exe (file missing)
O23 - Service: @%systemroot%\system32\fxsresm.dll,-118 (Fax) - Unknown owner - C:\Windows\system32\fxssvc.exe (file missing)
O23 - Service: Servizio di Google Update (gupdate) (gupdate) - Google Inc. - C:\Program Files (x86)\Google\Update\GoogleUpdate.exe
O23 - Service: Google Software Updater (gusvc) - Google - C:\Program Files (x86)\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files (x86)\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: @keyiso.dll,-100 (KeyIso) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: Process Monitor (LVPrcS64) - Logitech Inc. - C:\Program Files\Common Files\LogiShrd\LVMVFM\LVPrcSrv.exe
O23 - Service: McciCMService - Unknown owner - C:\Program Files (x86)\Common Files\Motive\McciCMService.exe (file missing)
O23 - Service: Distributed Transaction Coordinator (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: Performance Service (nTuneService) - NVIDIA - C:\Program Files (x86)\NVIDIA Corporation\nTune\nTuneService.exe
O23 - Service: NVIDIA Driver Helper Service (NVSvc) - Unknown owner - C:\Windows\system32\nvvsvc.exe (file missing)
O23 - Service: Archiviazione protetta (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: @%SystemRoot%\system32\snmptrap.exe,-3 (SNMPTRAP) - Unknown owner - C:\Windows\System32\snmptrap.exe (file missing)
O23 - Service: Spooler di stampa (Spooler) - Unknown owner - C:\Windows\System32\spoolsv.exe (file missing)
O23 - Service: Protezione software (sppsvc) - Unknown owner - C:\Windows\system32\sppsvc.exe (file missing)
O23 - Service: NVIDIA Stereoscopic 3D Driver Service (Stereo Service) - NVIDIA Corporation - C:\Program Files (x86)\NVIDIA Corporation\3D Vision\nvSCPAPISvr.exe
O23 - Service: @%SystemRoot%\system32\ui0detect.exe,-101 (UI0Detect) - Unknown owner - C:\Windows\system32\UI0Detect.exe (file missing)
O23 - Service: Update Center Service (UpdateCenterService) - NVIDIA - C:\Program Files (x86)\NVIDIA Corporation\System Update\UpdateCenterService.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\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: Servizio di condivisione in rete Windows Media Player (WMPNetworkSvc) - Unknown owner - C:\Program Files (x86)\Windows Media Player\wmpnetwk.exe (file missing)

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End of file - 9835 bytes

Per quello che possono valere le indicazioni di HJT, il log non presenta infezioni.
Poi, se hai formattato 2 volte, senza risultati apprezzabili, non saprei cosa dirti.
Prova a sostituire Comodo. (alle volte, se non configurato bene, rallenta il pc)