ciao, da ieri mi esce all'accensione questo avviso:

Errore durante l'avvio di C:\Windows\sistem32\sshnas21.dll
Impossibile trovare il modulo specficato.

posto mwb e hijack:

Malwarebytes' Anti-Malware 1.46
www.malwarebytes.org

Versione database: 4427

Windows 6.1.7600
Internet Explorer 8.0.7600.16385

14/08/2010 14:02:32
mbam-log-2010-08-14 (14-02-32).txt

Tipo di scansione: Scansione completa (C:\|)
Elementi esaminati: 356743
Tempo trascorso: 1 ore, 14 minuti, 59 secondi

Processi infetti in memoria: 0
Moduli di memoria infetti: 0
Chiavi di registro infette: 1
Valori di registro infetti: 1
Voci infette nei dati di registro: 0
Cartelle infette: 0
File infetti: 8

Processi infetti in memoria:
(Non sono stati rilevati elementi nocivi)

Moduli di memoria infetti:
(Non sono stati rilevati elementi nocivi)

Chiavi di registro infette:
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Handle (Malware.Trace) -> No action taken.

Valori di registro infetti:
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\metropolis (Trojan.Downloader) -> No action taken.

Voci infette nei dati di registro:
(Non sono stati rilevati elementi nocivi)

Cartelle infette:
(Non sono stati rilevati elementi nocivi)

File infetti:
C:\Windows\System32\sshnas21.dll (Trojan.Downloader) -> No action taken.
C:\Users\marika\AppData\Local\Temp\PbgQt3db.exe.part (Trojan.Downloader) -> No action taken.
C:\Users\marika\AppData\Local\Temp\sshnas21.dll (Trojan.Downloader) -> No action taken.
C:\Users\marika\AppData\Local\Temp\Xxm.exe (Trojan.Downloader) -> No action taken.
C:\Users\marika\AppData\Local\Temp\Xxn.exe (Trojan.Downloader) -> No action taken.
C:\Users\marika\AppData\Local\Temp\Xxp.exe (Trojan.Downloader) -> No action taken.
C:\Users\marika\AppData\Local\Temp\Xxr.exe (Trojan.Downloader) -> No action taken.
C:\Windows\SysWOW64\sshnas21.dll (Trojan.Downloader) -> No action taken.


Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 14:11:58, on 14/08/2010
Platform: Windows 7 (WinNT 6.00.3504)
MSIE: Internet Explorer v8.00 (8.00.7600.16385)
Boot mode: Normal

Running processes:
C:\Program Files (x86)\ASUS\SmartLogon\sensorsrv.exe
C:\Program Files (x86)\ASUS\ControlDeck\ControlDeckStartUp.exe
C:\Program Files (x86)\ASUS\ASUS Live Update\ALU.exe
C:\Program Files (x86)\ASUS\Wireless Console 3\wcourier.exe
C:\Program Files (x86)\Nokia\Nokia PC Suite 7\PCSuite.exe
C:\Program Files (x86)\ASUSTek\ASUSDVD 8\PDVD8Serv.exe
C:\Program Files (x86)\ASUS\ATK Hotkey\HControlUser.exe
C:\Program Files (x86)\ASUS\ATKOSD2\ATKOSD2.exe
C:\Program Files (x86)\ASUS\ATK Media\DMedia.exe
C:\Program Files (x86)\Vodafone\Vodafone Mobile Connect\Bin\MobileConnect.exe
C:\Program Files\Alwil Software\Avast5\AvastUI.exe
C:\Program Files (x86)\PC Connectivity Solution\Transports\NclMSBTSrvEx.exe
C:\Program Files (x86)\ASUS\ASUS Data Security Manager\ADSMTray.exe
C:\Windows\AsScrPro.exe
C:\Program Files (x86)\Cyberlink\Power2Go\CLMLSvc.exe
C:\Program Files (x86)\SeaMonkey\seamonkey.exe
C:\Program Files (x86)\Trend Micro\HiJackThis\HiJackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://asus.msn.com
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://asus.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
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: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files (x86)\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: Search Helper - {6EBF7485-159F-4bff-A14F-B9E3AAC4465B} - C:\Program Files (x86)\Microsoft\Search Enhancement Pack\Search Helper\SEPsearchhelperie.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: Windows Live Toolbar Helper - {E15A8DC0-8516-42A1-81EA-DC94EC1ACF10} - C:\Program Files (x86)\Windows Live\Toolbar\wltcore.dll
O3 - Toolbar: &Windows Live Toolbar - {21FA44EF-376D-4D53-9B0F-8A89D3229068} - C:\Program Files (x86)\Windows Live\Toolbar\wltcore.dll
O4 - HKLM\..\Run: [RemoteControl8] "C:\Program Files (x86)\ASUSTek\ASUSDVD 8\PDVD8Serv.exe"
O4 - HKLM\..\Run: [PDVD8LanguageShortcut] "C:\Program Files (x86)\ASUSTek\ASUSDVD 8\Language\Language.exe"
O4 - HKLM\..\Run: [UpdateLBPShortCut] "C:\Program Files (x86)\CyberLink\LabelPrint\MUITransfer\MUIStartMenu.exe" "C:\Program Files (x86)\CyberLink\LabelPrint" UpdateWithCreateOnce "Software\CyberLink\LabelPrint\2.5"
O4 - HKLM\..\Run: [UpdateP2GoShortCut] "C:\Program Files (x86)\CyberLink\Power2Go\MUITransfer\MUIStartMenu.exe" "C:\Program Files (x86)\CyberLink\Power2Go" UpdateWithCreateOnce "SOFTWARE\CyberLink\Power2Go\6.0"
O4 - HKLM\..\Run: [HControlUser] C:\Program Files (x86)\ASUS\ATK Hotkey\HControlUser.exe
O4 - HKLM\..\Run: [ATKOSD2] C:\Program Files (x86)\ASUS\ATKOSD2\ATKOSD2.exe
O4 - HKLM\..\Run: [ATKMEDIA] C:\Program Files (x86)\ASUS\ATK Media\DMedia.exe
O4 - HKLM\..\Run: [Setwallpaper] c:\programdata\SetWallpaper.cmd
O4 - HKLM\..\Run: [MobileConnect] %programfiles%\Vodafone\Vodafone Mobile Connect\Bin\MobileConnect.exe /silent
O4 - HKLM\..\Run: [avast5] "C:\Program Files\Alwil Software\Avast5\avastUI.exe" /nogui
O4 - HKCU\..\Run: [msnmsgr] "C:\Program Files (x86)\Windows Live\Messenger\msnmsgr.exe" /background
O4 - HKCU\..\Run: [PC Suite Tray] "C:\Program Files (x86)\Nokia\Nokia PC Suite 7\PCSuite.exe" -onlytray
O4 - HKCU\..\Run: [Metropolis] rundll32.exe C:\Windows\system32\sshnas21.dll,GetHandle
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')
O4 - Global Startup: Bluetooth.lnk = ?
O4 - Global Startup: FancyStart daemon.lnk = ?
O4 - Global Startup: SRS Premium Sound.lnk = ?
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~2\MICROS~1\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~2\MICROS~1\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: Invia immagine alla periferica &Bluetooth... - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie_ctx.htm
O8 - Extra context menu item: Invia pagina alla periferica &Bluetooth... - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie.htm
O9 - Extra button: Inserisci blog - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files (x86)\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra 'Tools' menuitem: Inserisci &blog in Windows Live Writer - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files (x86)\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra button: Invia a OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~2\MICROS~1\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: I&nvia a OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~2\MICROS~1\Office12\ONBttnIE.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~2\MICROS~1\Office12\REFIEBAR.DLL
O9 - Extra button: Invia a Bluetooth - {CCA281CA-C863-46ef-9331-5C8D4460577F} - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie.htm
O9 - Extra 'Tools' menuitem: Invia a periferica &Bluetooth... - {CCA281CA-C863-46ef-9331-5C8D4460577F} - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie.htm
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
O23 - Service: ADSM Service (ADSMService) - ASUSTek Computer Inc. - C:\Program Files (x86)\ASUS\ASUS Data Security Manager\ADSMSrv.exe
O23 - Service: AFBAgent - Unknown owner - C:\Windows\system32\FBAgent.exe (file missing)
O23 - Service: @%SystemRoot%\system32\Alg.exe,-112 (ALG) - Unknown owner - C:\Windows\System32\alg.exe (file missing)
O23 - Service: ASLDR Service (ASLDRService) - ASUS - C:\Program Files (x86)\ASUS\ATK Hotkey\ASLDRSrv.exe
O23 - Service: ATKGFNEX Service (ATKGFNEXSrv) - Unknown owner - C:\Program Files\ATKGFNEX\GFNEXSrv.exe
O23 - Service: avast! Antivirus - AVAST Software - C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
O23 - Service: avast! Mail Scanner - AVAST Software - C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
O23 - Service: avast! Web Scanner - AVAST Software - C:\Program Files\Alwil Software\Avast5\AvastSvc.exe
O23 - Service: Bluetooth Service (btwdins) - Broadcom Corporation. - C:\Program Files\WIDCOMM\Bluetooth Software\btwdins.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: @keyiso.dll,-100 (KeyIso) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: @comres.dll,-2797 (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: NVIDIA Display Driver Service (nvsvc) - Unknown owner - C:\Windows\system32\nvvsvc.exe (file missing)
O23 - Service: Oberon Media Game Console service (OberonGameConsoleService) - Unknown owner - C:\Program Files (x86)\Asus\Game Park\GameConsole\OberonGameConsoleService.exe
O23 - Service: @%systemroot%\system32\psbase.dll,-300 (ProtectedStorage) - Unknown owner - C:\Windows\system32\lsass.exe (file missing)
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - C:\Program Files (x86)\Cyberlink\Shared files\RichVideo.exe
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: ServiceLayer - Nokia - C:\Program Files (x86)\PC Connectivity Solution\ServiceLayer.exe
O23 - Service: @%SystemRoot%\system32\snmptrap.exe,-3 (SNMPTRAP) - Unknown owner - C:\Windows\System32\snmptrap.exe (file missing)
O23 - Service: @%systemroot%\system32\spoolsv.exe,-1 (Spooler) - Unknown owner - C:\Windows\System32\spoolsv.exe (file missing)
O23 - Service: @%SystemRoot%\system32\sppsvc.exe,-101 (sppsvc) - Unknown owner - C:\Windows\system32\sppsvc.exe (file missing)
O23 - Service: @%SystemRoot%\system32\ui0detect.exe,-101 (UI0Detect) - Unknown owner - C:\Windows\system32\UI0Detect.exe (file missing)
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: Vodafone Mobile Connect Service (VMCService) - Vodafone - C:\Program Files (x86)\Vodafone\Vodafone Mobile Connect\Bin\VMCService.exe
O23 - Service: @%systemroot%\system32\vssvc.exe,-102 (VSS) - Unknown owner - C:\Windows\system32\vssvc.exe (file missing)
O23 - Service: @%SystemRoot%\system32\Wat\WatUX.exe,-601 (WatAdminSvc) - Unknown owner - C:\Windows\system32\Wat\WatAdminSvc.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: @%PROGRAMFILES%\Windows Media Player\wmpnetwk.exe,-101 (WMPNetworkSvc) - Unknown owner - C:\Program Files (x86)\Windows Media Player\wmpnetwk.exe (file missing)

--
End of file - 11075 bytes

Ti sei beccata un trojan "rognosetto" (la DLL che risulta "introvabile", in realtà è un malware)... Vediamo se ci riesce di farlo fuori in questo modo:
Disabilita il Ripristino configurazione di sistema.
Poi, aggiorna a puntino sia Malwarebytes' AntiMalware che il tuo Avast!5.
Quindi, vai in Modalità Provvisoria.
Ivi giunta, lancia in scansione Malwarebytes' AntiMalware. Elimina tutte le voci maligne che Malwarebytes' ti rileverà.
Dopo di che, lancia in scansione anche Avast! e elimina anche tutte le voci maligne che ti dovessero venire, eventualmente, rilevate.
Dopo di che, torna in Modalità Normale e effettua una scansione online sul sito Housecall/Trendmicro. Se non ti verrà rilevato niente di "maligno", riattiva il Ripristino configurazione di sistema e poi procedi a creati un "punto di ripristino" manualmente.
Se non riusciamo a venirne a capo così... dovremo passare alle maniere forti (ma speriam di riuscire anche così)...

Perfetto, Marika. Sei stata brava! Mi fa proprio piacere.