Mi sono trovato un worm e non so che fare, ma ho anche il problema che in avvio mi compare questo errore: isdi.dll - applicazione di iaanotif.exe.
Vi invio il log di hijackthis dopo aver disattivato ripristino di sistema, riacceso e creato un punto di ripristino.

Logfile of HijackThis v1.99.0
Scan saved at 1.30.05, on 14/02/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16608)

Running processes:
C:\WINDOWS\System32\smss.exe
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\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\eHome\ehRecvr.exe
C:\WINDOWS\eHome\ehSched.exe
C:\Programmi\Google\Common\Google Updater\GoogleUpdaterService.exe
C:\Programmi\Intel\Intel Matrix Storage Manager\Iaantmon.exe
C:\Programmi\File comuni\LightScribe\LSSrvc.exe
C:\Programmi\File comuni\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\Programmi\Nero\Nero8\Nero BackItUp\NBService.exe
C:\Programmi\Eset\nod32krn.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\Programmi\Spyware Doctor\pctsAuxs.exe
C:\Programmi\Spyware Doctor\pctsSvc.exe
C:\WINDOWS\ehome\ehtray.exe
C:\WINDOWS\RTHDCPL.EXE
C:\Programmi\Intel\Intel Matrix Storage Manager\Iaanotif.exe
C:\WINDOWS\system32\rundll32.exe
C:\WINDOWS\system32\rundll32.exe
C:\WINDOWS\system32\rundll32.exe
C:\Programmi\Spyware Doctor\pctsTray.exe
C:\PROGRA~1\ALICET~1\SMARTB~1\MotiveSB.exe
C:\Programmi\Alice ti aiuta\vendors\AliceRE\content\template\driven_dev\syncer\McciTrayApp.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Windows Live\Messenger\MsnMsgr.Exe
C:\Program Files\Wcescomm.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\Alice ti aiuta\bin\mpbtn.exe
C:\Programmi\Google\Google Updater\GoogleUpdater.exe
C:\PROGRA~2\rapimgr.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\PPSOFT.DK\Ramdisk\Ramdisk.exe
C:\Programmi\WinZip\WZQKPICK.EXE
C:\WINDOWS\system32\MsPMSPSv.exe
C:\WINDOWS\ehome\mcrdsvc.exe
C:\Programmi\Intel\IntelDH\Intel(R) Quick Resume Technology Drivers\Elservice.exe
C:\WINDOWS\system32\dllhost.exe
C:\WINDOWS\System32\alg.exe
C:\WINDOWS\eHome\ehmsas.exe
C:\Programmi\File comuni\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Programmi\Windows Live Toolbar\msn_sl.exe
C:\Programmi\Internet Explorer\iexplore.exe
C:\Archivos de programa\HijackThis\HijackThis.exe
C:\Programmi\Internet Explorer\IEXPLORE.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://go.microsoft.com/fwlink/?LinkId=69157
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: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: MouseGest - {112AB43D-32C4-3B21-53BA-13A46743BC34} - C:\WINDOWS\system32\mousegex.dll
O2 - BHO: Skype add-on (mastermind) - {22BF413B-C6D2-4d91-82A9-A0F997BA588C} - C:\Programmi\Skype\Toolbars\Internet Explorer\SkypeIEPlugin.dll
O2 - BHO: Web Mon - {7428F943-BC4F-4A39-3B43-AB433C523B34} - C:\WINDOWS\system32\WebMon.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_03\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
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: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\programmi\google\googletoolbar3.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
O2 - BHO: Windows Live Toolbar Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Programmi\Windows Live Toolbar\msntb.dll
O3 - Toolbar: Adobe PDF - {47833539-D0C5-4125-9FA8-0819E2EAAC93} - C:\Programmi\Adobe\Acrobat 7.0\Acrobat\AcroIEFavClient.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\programmi\google\googletoolbar3.dll
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Programmi\Windows Live Toolbar\msntb.dll
O4 - HKLM\..\Run: [ehTray] C:\WINDOWS\ehome\ehtray.exe
O4 - HKLM\..\Run: [ftutil2] rundll32.exe ftutil2.dll,SetWriteCacheMode
O4 - HKLM\..\Run: [RTHDCPL] RTHDCPL.EXE
O4 - HKLM\..\Run: [IAAnotif] C:\Programmi\Intel\Intel Matrix Storage Manager\Iaanotif.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /installquiet /keeploaded /nodetect
O4 - HKLM\..\Run: [DMAScheduler] "c:\Programmi\HP DigitalMedia Archive\DMAScheduler.exe"
O4 - HKLM\..\Run: [Recguard] C:\WINDOWS\SMINST\RECGUARD.EXE
O4 - HKLM\..\Run: [HPBootOp] "C:\Programmi\Hewlett-Packard\HP Boot Optimizer\HPBootOp.exe" /run
O4 - HKLM\..\Run: [Reminder] "C:\Windows\Creator\Remind_XP.exe"
O4 - HKLM\..\Run: [HP Software Update] C:\Programmi\HP\HP Software Update\HPwuSchd2.exe
O4 - HKLM\..\Run: [TkBellExe] "C:\Programmi\File comuni\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [Acrobat Assistant 7.0] "C:\Programmi\Adobe\Acrobat 7.0\Distillr\Acrotray.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Programmi\QuickTime\bak\qttask.exe" -atboottime
O4 - HKLM\..\Run: [Adobe Photo Downloader] "C:\Programmi\Adobe\Photoshop Album Starter Edition\3.0\Apps\apdproxy.exe"
O4 - HKLM\..\Run: [Soundlibs] C:\WINDOWS\soundlib.exe
O4 - HKLM\..\Run: [PCSuiteTrayApplication] C:\Programmi\Nokia\Nokia PC Suite 6\LaunchApplication.exe -startup
O4 - HKLM\..\Run: [nod32kui] "C:\Programmi\Eset\nod32kui.exe" /WAITSERVICE
O4 - HKLM\..\Run: [WinampAgent] C:\Programmi\Winamp\winampa.exe
O4 - HKLM\..\Run: [NeroFilterCheck] C:\Programmi\File comuni\Nero\Lib\NeroCheck.exe
O4 - HKLM\..\Run: [NBKeyScan] "C:\Programmi\Nero\Nero8\Nero BackItUp\NBKeyScan.exe"
O4 - HKLM\..\Run: [TomTomHOME.exe] "C:\Programmi\TomTom HOME\TomTomHOME.exe" -s
O4 - HKLM\..\Run: [CnxTrApp] rundll32.exe "C:\Programmi\Conexant\Conexant USB Network\CnxTrApp.dll",AppEntry -REG "Conexant\Conexant USB Network"
O4 - HKLM\..\Run: [AdslTaskBar] rundll32.exe stmctrl.dll,TaskBar
O4 - HKLM\..\Run: [ISTray] "C:\Programmi\Spyware Doctor\pctsTray.exe"
O4 - HKLM\..\Run: [Motive SmartBridge] C:\PROGRA~1\ALICET~1\SMARTB~1\MotiveSB.exe
O4 - HKLM\..\Run: [AliceRE_McciTrayApp] C:\Programmi\Alice ti aiuta\vendors\AliceRE\content\template\driven_dev\syncer\McciTrayApp.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre1.6.0_03\bin\jusched.exe"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [swg] C:\Programmi\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Programmi\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [Orb] "C:\Programmi\Winamp Remote\bin\OrbTray.exe" /background
O4 - HKCU\..\Run: [H/PC Connection Agent] "C:\Program Files\Wcescomm.exe"
O4 - Startup: Adobe Gamma.lnk = C:\Programmi\File comuni\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Alice ti aiuta.lnk = C:\Programmi\Alice ti aiuta\bin\matcli.exe
O4 - Global Startup: Avvio veloce di Adobe Acrobat.lnk = ?
O4 - Global Startup: Google Updater.lnk = C:\Programmi\Google\Google Updater\GoogleUpdater.exe
O4 - Global Startup: Ramdisk.lnk = C:\Programmi\PPSOFT.DK\Ramdisk\Ramdisk.exe
O4 - Global Startup: WinZip Quick Pick.lnk = C:\Programmi\WinZip\WZQKPICK.EXE
O8 - Extra context menu item: &Windows Live Search - res://C:\Programmi\Windows Live Toolbar\msntb.dll/search.htm
O8 - Extra context menu item: Add to Windows &Live Favorites - http://favorites.live.com/quickadd.aspx
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0\bin\npjpi160.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0\bin\npjpi160.dll
O9 - Extra button: Inserisci blog - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Programmi\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra 'Tools' menuitem: Inserisci &blog in Windows Live Writer - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Programmi\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra button: Create Mobile Favorite - {2EAF5BB1-070F-11D3-9307-00C04FAE2D4F} - C:\PROGRA~2\INetRepl.dll
O9 - Extra button: (no name) - {2EAF5BB2-070F-11D3-9307-00C04FAE2D4F} - C:\PROGRA~2\INetRepl.dll
O9 - Extra 'Tools' menuitem: Crea preferiti portatile... - {2EAF5BB2-070F-11D3-9307-00C04FAE2D4F} - C:\PROGRA~2\INetRepl.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~3\OFFICE11\REFIEBAR.DLL
O9 - Extra button: Guida alla connessione - {E2D4D26B-0180-43a4-B05F-462D6D54C789} - C:\WINDOWS\PCHEALTH\HELPCTR\Vendors\CN=Hewlett-Packard,L=Cupertino,S=Ca,C=US\IEButton\support.htm
O9 - Extra 'Tools' menuitem: Guida alla connessione - {E2D4D26B-0180-43a4-B05F-462D6D54C789} - C:\WINDOWS\PCHEALTH\HELPCTR\Vendors\CN=Hewlett-Packard,L=Cupertino,S=Ca,C=US\IEButton\support.htm
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
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
O11 - Options group: [INTERNATIONAL] International*
O16 - DPF: {02BF25D5-8C17-4B23-BC80-D3488ABDDC6B} (QuickTime Object) - http://a1540.g.akamai.net/7/1540/52/20061205/qtinstall.info.apple.com/qtactivex/qtplugin.cab
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://update.microsoft.com/microsoftupdate/v6/V5Controls/en/x86/client/muweb_site.cab?1163236529816
O17 - HKLM\System\CCS\Services\Tcpip\..\{C0B7979C-9E70-4BB5-B861-F66923EFD0D0}: NameServer = 85.37.17.10 85.38.28.86
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\WI1F86~1\MESSEN~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\WI1F86~1\MESSEN~1\MSGRAP~1.DLL
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\SKYPE4~1.DLL
O18 - Protocol: wlmailhtml - {03C514A3-1EFB-4856-9F99-10D7BE1653C0} - C:\Programmi\Windows Live\Mail\mailcomm.dll
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: Adobe LM Service - Adobe Systems - C:\Programmi\File comuni\Adobe Systems Shared\Service\Adobelmsvc.exe
O23 - Service: Intel(R) Quick Resume technology - Intel Corporation - C:\Programmi\Intel\IntelDH\Intel(R) Quick Resume Technology Drivers\Elservice.exe
O23 - Service: Google Updater Service - Google - C:\Programmi\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: Intel(R) Matrix Storage Event Monitor - Intel Corporation - C:\Programmi\Intel\Intel Matrix Storage Manager\Iaantmon.exe
O23 - Service: InstallDriver Table Manager - Macrovision Corporation - C:\Programmi\File comuni\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: LEC TranslateDotNet Server - Unknown - C:\Programmi\Power Translator\LogoMedia TranslateDotNet Server.exe (file missing)
O23 - Service: LightScribeService Direct Disc Labeling Service - Hewlett-Packard Company - C:\Programmi\File comuni\LightScribe\LSSrvc.exe
O23 - Service: Nero BackItUp Scheduler 3 - Nero AG - C:\Programmi\Nero\Nero8\Nero BackItUp\NBService.exe
O23 - Service: NMIndexingService - Nero AG - C:\Programmi\File comuni\Nero\Lib\NMIndexingService.exe
O23 - Service: NOD32 Kernel Service - Eset - C:\Programmi\Eset\nod32krn.exe
O23 - Service: NVIDIA Display Driver Service - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: PC Tools Auxiliary Service - PC Tools - C:\Programmi\Spyware Doctor\pctsAuxs.exe
O23 - Service: PC Tools Security Service - PC Tools - C:\Programmi\Spyware Doctor\pctsSvc.exe
O23 - Service: ServiceLayer - Nokia. - C:\Programmi\PC Connectivity Solution\ServiceLayer.exe


Per eliminare il virus devo farlo in modalità provvisoria?
Grazie. nec

Ciao nec188 .
Prima di tutto segui il percorso di questa chiave(Start\Esegui\digita: regedit\ok\
Hkey_Local_Machine\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\ WindowsServicesStartup = "%Temp dir%\svchost.exe 1" Si devono eliminare le voci in rosso. (vai sopra le voci, clicchi con il tasto destro,e clicca Elimina.) Se non lo fai ,quella chiave rigenera il virus ad ogni avvio.
Poi:
Assicurati di avere accesso a file e cartelle nascosti
(Pannello di controllo-> Opzioni Cartella-> Visualizzazione)
1) Metti la spunta su: Visualizza file e cartelle nascoste
2) Togli la spunta: nascondi file protetti di sistema

Disattiva il ripristino configurazione di sistema http://guide.aiutamici.com/guide?C1=7&C2=68&ID=80121

Se non sai "fixare"le voci,segui questa guida dettagliata: http://www.aiutaamici.com/software?ID=11175

Avvia in modalità provvisoria http://guide.aiutamici.com/guide?C1=7&C2=68&ID=80122

Avvia hijackthis, metti la spunta alle voci che andrò ad elencarti e con tutte le applicazioni chiuse e disconnesso da Internet,premi su fix checked
O2 - BHO: MouseGest - {112AB43D-32C4-3B21-53BA-13A46743BC34} - C:\WINDOWS\system32\mousegex.dll
O2 - BHO: Web Mon - {7428F943-BC4F-4A39-3B43-AB433C523B34} - C:\WINDOWS\system32\WebMon.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O4 - HKLM\..\Run: [Soundlibs] C:\WINDOWS\soundlib.exe

Trova e cancella i file in rosso:
C:\WINDOWS\system32\mousegex.dll
C:\WINDOWS\system32\WebMon.dll
C:\WINDOWS\soundlib.exe

Scarica VIRIT :
http://www.tgsoft.it/italy/download.htm lo aggiorni (cliccando sulla parabola in alto) e lo fai girare in Modalità Provvisoria (è molto importante).

Scarica Spy-Bot da qui http://www.aiutaamici.com/software?ID=10831 e fai una scansione sempre in Modalità Provvisoria.

Dai una pulita (registro compreso)con questo http://www.aiutaamici.com/software?ID=11223

Riavvia il computer normalmente.
Alla fine fai una scansione on-line con questo; http://www.pandasoftware.com/activescan/it/activescan_principal.htm

Ricordati di rinascondere le cartelle di sistema;
riattiva il ripristino configurazione di sistema e, se tutto è a posto, creane uno nuovo.