Hola, una amiga tuvo un troyano y después de seguir las indicaciones del foro parece que todo está en orden, os pongo su log de hijackthis por si veis algo que no esté bien,

gracias
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Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 12:10:49 AM, on 2/4/2010
Platform: Windows Vista SP1 (WinNT 6.00.1905)
MSIE: Internet Explorer v7.00 (7.00.6001.18000)
Boot mode: Normal

Running processes:
C:\windows\system32\Dwm.exe
C:\windows\Explorer.EXE
C:\windows\system32\taskeng.exe
C:\Windows\System32\igfxtray.exe
C:\Windows\System32\hkcmd.exe
C:\Windows\System32\igfxpers.exe
C:\Program Files\Analog Devices\Core\smax4pnp.exe
C:\Program Files\Intel\Intel Matrix Storage Manager\IAAnotif.exe
C:\Program Files\PDF Complete\pdfsty.exe
C:\Program Files\Hewlett-Packard\HP ProtectTools Security Manager\pthosttr.exe
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\Hewlett-Packard\HP Wireless Assistant\HPWAMain.exe
C:\Program Files\Java\jre1.6.0_01\bin\jusched.exe
C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\QLBCTRL.exe
C:\Program Files\HP\HP Software Update\hpwuSchd2.exe
C:\Program Files\AVG\AVG8\avgtray.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Common Files\LightScribe\LightScribeControlPanel.exe
C:\Users\mar\AppData\Roaming\Dropbox\bin\Dropbox.e xe
C:\Windows\system32\igfxsrvc.exe
C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\VolCtrl.exe
C:\Program Files\Hewlett-Packard\HP wireless Assistant\WiFiMsg.EXE
C:\Program Files\Hewlett-Packard\Shared\HpqToaster.exe
C:\Program Files\Synaptics\SynTP\SynTPHelper.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe
C:\windows\system32\SearchFilterHost.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = Bing
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = Google
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = MSN.com
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = Bing
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = Bing
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = MSN.com
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: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Program Files\AVG\AVG8\avgssie.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O3 - Toolbar: (no name) - {0BF43445-2F28-4351-9252-17FE6E806AA0} - (no file)
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [IgfxTray] C:\Windows\system32\igfxtray.exe
O4 - HKLM\..\Run: [HotKeysCmds] C:\Windows\system32\hkcmd.exe
O4 - HKLM\..\Run: [Persistence] C:\Windows\system32\igfxpers.exe
O4 - HKLM\..\Run: [SoundMAXPnP] C:\Program Files\Analog Devices\Core\smax4pnp.exe
O4 - HKLM\..\Run: [IAAnotif] C:\Program Files\Intel\Intel Matrix Storage Manager\iaanotif.exe
O4 - HKLM\..\Run: [PDF Complete] "C:\Program Files\PDF Complete\pdfsty.exe"
O4 - HKLM\..\Run: [PTHOSTTR] C:\Program Files\Hewlett-Packard\HP ProtectTools Security Manager\PTHOSTTR.EXE /Start
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [hpWirelessAssistant] C:\Program Files\Hewlett-Packard\HP Wireless Assistant\HPWAMain.exe
O4 - HKLM\..\Run: [HP Health Check Scheduler] c:\Program Files\Hewlett-Packard\HP Health Check\HPHC_Scheduler.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0_01\bin\jusched.exe"
O4 - HKLM\..\Run: [QlbCtrl.exe] C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\QlbCtrl.exe /Start
O4 - HKLM\..\Run: [HP Software Update] c:\Program Files\Hp\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [AVG8_TRAY] C:\PROGRA~1\AVG\AVG8\avgtray.exe
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter
O4 - HKCU\..\Run: [LightScribe Control Panel] C:\Program Files\Common Files\LightScribe\LightScribeControlPanel.exe -hidden
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 - Startup: Dropbox.lnk = C:\Users\mar\AppData\Roaming\Dropbox\bin\Dropbox.e xe
O4 - Global Startup: DVD Check.lnk = C:\Program Files\InterVideo\DVD Check\DVDCheck.exe
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: Enviar imagen al dispositivo &Bluetooth... - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie_ctx.htm
O8 - Extra context menu item: Enviar página al dispositivo &Bluetooth... - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\REFIEBAR.DLL
O9 - Extra button: @btrez.dll,-4015 - {CCA281CA-C863-46ef-9331-5C8D4460577F} - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie.htm
O9 - Extra 'Tools' menuitem: @btrez.dll,-12650 - {CCA281CA-C863-46ef-9331-5C8D4460577F} - C:\Program Files\WIDCOMM\Bluetooth Software\btsendto_ie.htm
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search && Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O13 - Gopher Prefix:
O16 - DPF: {90C9629E-CD32-11D3-BBFB-00105A1F0D68} (InstallShield International Setup Player) - http://www.lizardtech.com/download/f...all/isetup.cab
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Program Files\AVG\AVG8\avgpp.dll
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\COMMON~1\Skype\SKYPE4~1.DLL
O20 - AppInit_DLLs: avgrsstx.dll
O20 - Winlogon Notify: DeviceNP - C:\windows\SYSTEM32\DeviceNP.dll
O23 - Service: Andrea ADI Filters Service (AEADIFilters) - Andrea Electronics Corporation - C:\windows\system32\AEADISRV.EXE
O23 - Service: Agere Modem Call Progress Audio (AgereModemAudio) - Agere Systems - C:\Windows\system32\agrsmsvc.exe
O23 - Service: ArcGIS License Manager - Unknown owner - C:\PROGRA~1\ESRI\License\arcgis9x\lmgrd.exe
O23 - Service: AVG Free8 WatchDog (avg8wd) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
O23 - Service: Com4QLBEx - Hewlett-Packard Development Company, L.P. - C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\Com4QLBEx.exe
O23 - Service: EngineServer - McAfee, Inc. - C:\PROGRA~1\McAfee\MANAGE~1\VScan\ENGINE~1.EXE
O23 - Service: HP ProtectTools Device Locking / Auditing (FLCDLOCK) - Hewlett-Packard Ltd - C:\Windows\system32\flcdlock.exe
O23 - Service: Google Update Service (gupdate) (gupdate) - Google Inc. - C:\Program Files\Google\Update\GoogleUpdate.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: Intel(R) Matrix Storage Event Monitor (IAANTMON) - Intel Corporation - C:\Program Files\Intel\Intel Matrix Storage Manager\IAANTMon.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: IviRegMgr - InterVideo - C:\Program Files\Common Files\InterVideo\RegMgr\iviRegMgr.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - C:\Program Files\Common Files\LightScribe\LSSrvc.exe
O23 - Service: McShield - McAfee, Inc. - C:\PROGRA~1\McAfee\MANAGE~1\VScan\McShield.exe
O23 - Service: McAfee Virus and Spyware Protection Service (myAgtSvc) - McAfee, Inc. - C:\Program Files\McAfee\Managed VirusScan\Agent\myAgtSvc.Exe
O23 - Service: PDF Document Manager (pdfcDispatcher) - PDF Complete Inc - C:\Program Files\PDF Complete\pdfsvc.exe
O23 - Service: RoxMediaDB10 - Sonic Solutions - c:\Program Files\Common Files\Roxio Shared\10.0\SharedCOM\RoxMediaDB10.exe
O23 - Service: Remote Procedure Call (RPC) Net (rpcnet) - Absolute Software Corp. - C:\windows\system32\rpcnet.exe
O23 - Service: SBSD Security Center Service (SBSDWSCService) - Safer Networking Ltd. - C:\Program Files\Spybot - Search & Destroy\SDWinSec.exe
O23 - Service: Sentinel Protection Server (SentinelProtectionServer) - SafeNet, Inc - C:\Program Files\Common Files\SafeNet Sentinel\Sentinel Protection Server\WinNT\spnsrvnt.exe
O23 - Service: stllssvr - MicroVision Development, Inc. - c:\Program Files\Common Files\SureThing Shared\stllssvr.exe

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End of file - 9918 bytes

Windows Vista ya dispone del SP2. Deberías de empezar por la instalación de dicho servi pack y actualizaciones posteriores.

Un saludo

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