Vi posto il log di Hijack, premetto che:
-ho il sistema ripulito
-ho provato a fare scansioni con il mio antivirus (TrendMicro), ho scaricato e installato AVG 8, ad-aware e tutti vanno in crash quando avviano il servizio di scansione
-Ho usato Kaspersky online e mi è crashato Firefox
-Se provo ad accedere ad una qualsiasi cartella del pc tramite Risorse, explorer.exe va in crash

Se potete dateci un occhiata grazie

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 10.50.22, on 14/11/2008
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16735)
Boot mode: Normal

Running processes:
C:\WINDOWS\system32\csrss.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\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
C:\WINDOWS\system32\inetsrv\inetinfo.exe
C:\WINDOWS\system32\svchost.exe
C:\PROGRA~1\AVG\AVG8\avgrsx.exe
C:\PROGRA~1\AVG\AVG8\avgtray.exe
C:\WINDOWS\system32\ctfmon.exe
C:\WINDOWS\System32\alg.exe
C:\Programmi\Trend Micro\HijackThis\HijackThis.exe
C:\WINDOWS\explorer.exe
C:\WINDOWS\system32\wbem\wmiprvse.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://g.msn.com/0SEENUS/SAOS01?FORM=TOOLBR
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://g.msn.com/0SEENUS/SAOS01?FORM=TOOLBR
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://it.msn.com
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 Explorer\SearchURL,(Default) = http://g.msn.com/0SEENUS/SAOS01?FORM=TOOLBR
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Programmi\AVG\AVG8\avgssie.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_05\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\Programmi\AVG\AVG8\avgtoolbar.dll
O2 - BHO: AcroIEToolbarHelper Class - {AE7CD045-E861-484f-8273-0445EE161910} - C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Programmi\Google\GoogleToolbarNotifier\2.1.1119 .1736\swg.dll
O3 - Toolbar: Adobe PDF - {47833539-D0C5-4125-9FA8-0819E2EAAC93} - C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll
O3 - Toolbar: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\Programmi\AVG\AVG8\avgtoolbar.dll
O4 - HKLM\..\Run: [C:\WINDOWS\system32\kdkph.exe] C:\WINDOWS\system32\kdkph.exe
O4 - HKLM\..\Run: [AVG8_TRAY] C:\PROGRA~1\AVG\AVG8\avgtray.exe
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [eMuleAutoStart] C:\Programmi\eMule\emule.exe -AutoStart
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')
O8 - Extra context menu item: Converti destinazione link in Adobe PDF - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECapture.html
O8 - Extra context menu item: Converti destinazione link in file PDF esistente - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppend.html
O8 - Extra context menu item: Converti i link selezionati in Adobe PDF - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECaptureSelLinks.html
O8 - Extra context menu item: Converti i link selezionati in file PDF esistente - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppendSelLinks.html
O8 - Extra context menu item: Converti in Adobe PDF - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECapture.html
O8 - Extra context menu item: Converti nel file PDF esistente - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppend.html
O8 - Extra context menu item: Converti selezione in Adobe PDF - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIECapture.html
O8 - Extra context menu item: Converti selezione in file PDF esistente - res://C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll/AcroIEAppend.html
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\REFIEBAR.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: {02BF25D5-8C17-4B23-BC80-D3488ABDDC6B} (QuickTime Object) - http://appldnld.apple.com.edgesuite....x/qtplugin.cab
O16 - DPF: {0CCA191D-13A6-4E29-B746-314DEE697D83} (Facebook Photo Uploader 5) - http://upload.facebook.com/controls/...oUploader5.cab
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://www.update.microsoft.com/wind...?1204714833734
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://www.update.microsoft.com/micr...?1204724590937
O16 - DPF: {7FC1B346-83E6-4774-8D20-1A6B09B0E737} (Windows Live Photo Upload Control) - http://bananeatomiche.spaces.live.co...d/MsnPUpld.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/ge...sh/swflash.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{4CBAA140-11B7-4D01-AF45-09DFAD8EDC6F}: NameServer = 85.255.112.102;85.255.112.168
O17 - HKLM\System\CS1\Services\Tcpip\..\{4CBAA140-11B7-4D01-AF45-09DFAD8EDC6F}: NameServer = 85.255.112.102;85.255.112.168
O17 - HKLM\System\CS2\Services\Tcpip\..\{4CBAA140-11B7-4D01-AF45-09DFAD8EDC6F}: NameServer = 151.99.125.1
O17 - HKLM\System\CS3\Services\Tcpip\..\{4CBAA140-11B7-4D01-AF45-09DFAD8EDC6F}: NameServer = 85.255.112.102;85.255.112.168
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Programmi\AVG\AVG8\avgpp.dll
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\SKYPE4~1.DLL
O20 - AppInit_DLLs: avgrsstx.dll
O23 - Service: Lavasoft Ad-Aware Service (aawservice) - Lavasoft - C:\Programmi\Lavasoft\Ad-Aware\aawservice.exe
O23 - Service: AVG Free8 WatchDog (avg8wd) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
O23 - Service: ServiceLayer - Nokia. - C:\Programmi\Nokia\PC Connectivity Solution\ServiceLayer.exe

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