Alla scansione di AVG mi appare questa voce "SHELL32.dll CHANGE C:\windows\system32\shell32"....
al termine della scansione però mi dice "no threats found"...ne deduco che la voce che rileva non è un virus, cos'è allora?
di seguito c'è il Log se potete dargli un occhiata per cortesia..

Logfile of HijackThis v1.99.1
Scan saved at 19.59.21, on 25/11/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

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\ZoneLabs\vsmon.exe
C:\WINDOWS\system32\LEXBCES.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\LEXPPS.EXE
C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\Mixer.exe
C:\Programmi\File comuni\Real\Update_OB\realsched.exe
C:\WINDOWS\tsnpstd3.exe
C:\Programmi\Zone Labs\ZoneAlarm\zlclient.exe
C:\Programmi\Java\jre1.6.0_01\bin\jusched.exe
C:\PROGRA~1\Grisoft\AVG7\avgcc.exe
C:\Programmi\Real\RealPlayer\RealPlay.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Spybot - Search & Destroy\TeaTimer.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Hijackthis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.libero.it/
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: Skype add-on (mastermind) - {22BF413B-C6D2-4d91-82A9-A0F997BA588C} - C:\Programmi\Skype\Toolbars\Internet Explorer\SkypeIEPlugin.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_01\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O4 - HKLM\..\Run: [C-Media Mixer] Mixer.exe /startup
O4 - HKLM\..\Run: [TkBellExe] "C:\Programmi\File comuni\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [tsnpstd3] C:\WINDOWS\tsnpstd3.exe
O4 - HKLM\..\Run: [ZoneAlarm Client] "C:\Programmi\Zone Labs\ZoneAlarm\zlclient.exe"
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre1.6.0_01\bin\jusched.exe"
O4 - HKLM\..\Run: [AVG7_CC] C:\PROGRA~1\Grisoft\AVG7\avgcc.exe /STARTUP
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Programmi\Spybot - Search & Destroy\TeaTimer.exe
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra button: Skype - {77BF5300-1474-4EC7-9980-D32B190E9B07} - C:\Programmi\Skype\Toolbars\Internet Explorer\SkypeIEPlugin.dll
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe (file missing)
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe (file missing)
O16 - DPF: {0E8D0700-75DF-11D3-8B4A-0008C7450C4A} (DjVuCtl Class) - http://downloadcenter.samsung.com/content/common/cab/DjVuControlLite_EN.cab
O16 - DPF: {7FC1B346-83E6-4774-8D20-1A6B09B0E737} (Windows Live Photo Upload Control) - http://cid-aaa4e7dc9c24ca02.spaces.live.com/PhotoUpload/MsnPUpld.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{C443E4A5-B55B-46E6-A4F9-44A623CC94BE}: NameServer = 85.37.17.16 85.38.28.68
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\SKYPE4~1.DLL
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: Apple Mobile Device - Apple, Inc. - C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: AVG7 Alert Manager Server (Avg7Alrt) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
O23 - Service: AVG7 Update Service (Avg7UpdSvc) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Programmi\Google\Common\Google Updater\GoogleUpdaterService.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: LexBce Server (LexBceS) - Lexmark International, Inc. - C:\WINDOWS\system32\LEXBCES.EXE
O23 - Service: TrueVector Internet Monitor (vsmon) - Zone Labs, LLC - C:\WINDOWS\system32\ZoneLabs\vsmon.exe

Quell'avviso non è una sciagura (è capitato anche a me). E' dovuto a qualche aggiornamento non a presenza di virus.

Per evitare questa segnalazione apri AVG <b>Test Center</b> clicca su <b>F3</b> e digli che accetti i cambiamenti (<b>Confirm changes</b>. Poi vai in C:\ e cancella <b>AVG7QT.DAT</b>. Riavvia, il computer ne creerà uno nuovo e l'avviso dovrebbe sparire per sempre.

Ciao,fammi sapere.

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