He realizado todos los pasos para quitar la pag mebuscas, he logrado poner google pero sigue realizando intentos de introducirla cual seria el paso siguiente, la bloqueo con spibot s&d. Os envio el log. gracias.

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 19:23:22, on 27/12/2007
Platform: Windows Vista (WinNT 6.00.1904)
MSIE: Internet Explorer v7.00 (7.00.6000.16575)
Boot mode: Safe mode

Running processes:
C:\Windows\Explorer.EXE
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

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.mbuscas.com/buscador.php?id=3
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://ie.redirect.hp.com/svs/rdr?TYPE=3&tp=iehome&locale=ES_ES&c=71&bd=Pavilion&pf=laptop
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://ie.redirect.hp.com/svs/rdr?TYPE=3&tp=iehome&locale=ES_ES&c=71&bd=Pavilion&pf=laptop
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O1 - Hosts: ::1 localhost
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {1E8A6170-7264-4D0F-BEAE-D42A53123C75} - C:\Program Files\Common Files\Symantec Shared\coShared\Browser\1.0\NppBho.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Aplicación auxiliar de inicio de sesión - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar1.dll
O2 - BHO: Windows Live Toolbar Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O3 - Toolbar: Show Norton Toolbar - {90222687-F593-4738-B738-FBEE9C7B26DF} - C:\Program Files\Common Files\Symantec Shared\coShared\Browser\1.0\UIBHO.dll
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar1.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [ccApp] "C:\Program Files\Common Files\Symantec Shared\ccApp.exe"
O4 - HKLM\..\Run: [osCheck] "C:\Program Files\Norton Internet Security\osCheck.exe"
O4 - HKLM\..\Run: [QPService] "C:\Program Files\HP\QuickPlay\QPService.exe"
O4 - HKLM\..\Run: [HP Software Update] C:\Program Files\Hp\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [QlbCtrl] %ProgramFiles%\Hewlett-Packard\HP Quick Launch Buttons\QlbCtrl.exe /Start
O4 - HKLM\..\Run: [HP Health Check Scheduler] C:\Program Files\Hewlett-Packard\HP Health Check\HPHC_Scheduler.exe
O4 - HKLM\..\Run: [WAWifiMessage] %ProgramFiles%\Hewlett-Packard\HP Wireless Assistant\WiFiMsg.exe
O4 - HKLM\..\Run: [hpWirelessAssistant] %ProgramFiles%\Hewlett-Packard\HP Wireless Assistant\HPWAMain.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0\bin\jusched.exe"
O4 - HKLM\..\Run: [NvSvc] RUNDLL32.EXE C:\Windows\system32\nvsvc.dll,nvsvcStart
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\Windows\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\Windows\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [Symantec PIF AlertEng] "C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe" /a /m "C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\AlertEng.dll"
O4 - HKLM\..\RunOnce: [Launcher] %WINDIR%\SMINST\launcher.exe
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [ehTray.exe] C:\Windows\ehome\ehTray.exe
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - HKCU\..\Run: [updateMgr] C:\Program Files\Adobe\Acrobat 7.0\Reader\AdobeUpdateManager.exe AcRdB7_0_5
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [Rundll32] c:\windows\system32\RUNDDLL32.exe
O4 - HKCU\..\Run: [SpyBrowser] "C:\Program Files\SpyBro\SpyBro.exe" /autostart
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\1.2.1128.5462\G oogleToolbarNotifier.exe
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICIO LOCAL')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'SERVICIO LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'Servicio de red')
O4 - HKUS\S-1-5-18\..\Run: [msnmsgr] "C:\Program Files\Windows Live\Messenger\msnmsgr.exe" /background (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [msnmsgr] "C:\Program Files\Windows Live\Messenger\msnmsgr.exe" /background (User 'Default user')
O4 - Global Startup: Inicio rápido de Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O6 - HKCU\Software\Policies\Microsoft\Internet Explorer\Restrictions present
O8 - Extra context menu item: &Windows Live Search - res://C:\Program Files\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:\Program Files\Java\jre1.6.0\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Consola de Sun Java - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0\bin\ssv.dll
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O13 - Gopher Prefix:
O16 - DPF: {0EB0E74A-2A76-4AB3-A7FB-9BD8C29F7F75} (CKAVWebScan Object) - http://www.kaspersky.com/kos/spanish/kavwebscan_unicode.cab
O23 - Service: Ad-Aware 2007 Service (aawservice) - Lavasoft AB - C:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
O23 - Service: AddFiltr - Hewlett-Packard Development Company, L.P. - C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\AddFiltr.exe
O23 - Service: Boonty Games - BOONTY - C:\Program Files\Common Files\BOONTY Shared\Service\Boonty.exe
O23 - Service: Symantec Event Manager (ccEvtMgr) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe
O23 - Service: Symantec Settings Manager (ccSetMgr) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe
O23 - Service: CyberLink Background Capture Service (CBCS) (CLCapSvc) - Unknown owner - C:\Program Files\HP\QuickPlay\Kernel\TV\CLCapSvc.exe
O23 - Service: CyberLink Task Scheduler (CTS) (CLSched) - Unknown owner - C:\Program Files\HP\QuickPlay\Kernel\TV\CLSched.exe
O23 - Service: Symantec Lic NetConnect service (CLTNetCnService) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe
O23 - Service: COM Host (comHost) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\VAScanner\comHost.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: HP Health Check Service - Hewlett-Packard - C:\Program Files\Hewlett-Packard\HP Health Check\hphc_service.exe
O23 - Service: hpqwmiex - Hewlett-Packard Development Company, L.P. - C:\Program Files\Hewlett-Packard\Shared\hpqwmiex.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Roxio\Roxio MyDVD Basic v9\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: Validación de contraseña de Symantec IS (ISPwdSvc) - Symantec Corporation - C:\Program Files\Norton Internet Security\isPwdSvc.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - C:\Program Files\Common Files\LightScribe\LSSrvc.exe
O23 - Service: LiveUpdate - Symantec Corporation - C:\PROGRA~1\Symantec\LIVEUP~1\LUCOMS~1.EXE
O23 - Service: LiveUpdate Notice Service Ex (LiveUpdate Notice Ex) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe
O23 - Service: LiveUpdate Notice Service - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe
O23 - Service: Programador de LiveUpdate automático - Symantec Corporation - C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
O23 - Service: RoxMediaDB9 - Sonic Solutions - C:\Program Files\Common Files\Roxio Shared\9.0\SharedCOM\RoxMediaDB9.exe
O23 - Service: SBSD Security Center Service (SBSDWSCService) - Safer Networking Ltd. - C:\Program Files\Spybot - Search & Destroy\SDWinSec.exe
O23 - Service: stllssvr - MicroVision Development, Inc. - C:\Program Files\Common Files\SureThing Shared\stllssvr.exe
O23 - Service: Symantec Core LC - Unknown owner - C:\Program Files\Common Files\Symantec Shared\CCPD-LC\symlcsvc.exe
O23 - Service: Symantec AppCore Service (SymAppCore) - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\AppCore\AppSvc32.exe
O23 - Service: XAudioService - Conexant Systems, Inc. - C:\Windows\system32\DRIVERS\xaudio.exe

--
End of file - 10150 bytes

Hola pablomedail, te doy la bienvenida al Foro de InfoSpyware.

Paso 1- Descarga estas herramientas pero no las ejecutes aun:
DelPSGuard 4.8.6 (http://www.forospyware.com/t4239.html)
SUPERAntiSpyware (http://www.infospyware.com/Anti-Spywares.htm)

Paso 2- Reinicia eh inicia en "Modo a prueba de fallos" (modo seguro) (http://www.forospyware.com/t68195.html#post292284)

Paso 3- Con todos los programas cerrados ejecuta HijackThis y dale "FIX Cheked" a estas entradas:


O4 - HKCU\..\Run: [Rundll32] c:\windows\system32\RUNDDLL32.exe

O4 - HKCU\..\Run: [SpyBrowser] "C:\Program Files\SpyBro\SpyBro.exe" /autostart


Paso 4- Ejecuta estas herramientas, de a una:
DelPSGuard.exe <- Guarda su reporte.
SUPERAntiSpyware

Paso 5- Descarga CCleaner (http://www.forospyware.com/t105564.html) y ejecútalo usando primero su opción de "Limpiador" para borrar cookies, temporales de Internet y todos los archivos que este te muestre como obsoletos, y luego usa su opción de "Registro" para limpiar todo el registro de Windows (haciendo copia de seguridad).


Reinicia y nos contas los resultados junto a un nuevo reporte de HJT y DelPSGuard.

Salu2