Gracias por querer ayudarme, he seguido tus pasos pero todo sigue igual, l línea O4 que me indicaste fix cheked se elimina de momento pero vuele al reiniciar la maquina como verás en el log que te mando. Por otro lado, el famoso archivo smss.exe no me aparece en la carpeta mensionada, ya lo busqué y me reporta la maquina que no existe tal archio. Espero tu respuesta y comentarios al respecto, para solucionar mi problema. Gracias de nuevo. Aquí está el log:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:53:06 a.m., on 15/12/2007
Platform: Windows Vista (WinNT 6.00.1904)
MSIE: Internet Explorer v7.00 (7.00.6000.16385)
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 = about:blank
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O2 - BHO: Aplicación auxiliar de vínculos de Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
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
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: [CorelDRAW Graphics Suite 11b] C:\Program Files\Corel\Corel Graphics 12\Languages\EN\Programs\Registration.exe /title="CorelDRAW Graphics Suite 12" /date=120107 serial=DR12WTX-9999998-YSP lang=EN
O4 - HKLM\..\Run: [nod32kui] "C:\Program Files\Eset\nod32kui.exe" /WAITSERVICE
O4 - HKLM\..\Run: [LManager] C:\PROGRA~1\LAUNCH~1\LManager.exe
O4 - HKLM\..\Run: [AMTray.exe] "C:\Acer\Empowering Technology\amtray.exe"
O4 - HKLM\..\Run: [ZPdtWzdVitaKey MC3000] "C:\Program Files\Acer\Acer Bio-Protection fingerprint solution\PdtWzd.exe" show
O4 - HKLM\..\Run: [lxbmmon.exe] "C:\Program Files\Lexmark 4200 Series\lxbmmon.exe"
O4 - HKLM\..\Run: [Lexmark 4200 Series Fax Server] "C:\Program Files\Lexmark 4200 Series\fm3032.exe" /s
O4 - HKLM\..\Run: [!AVG Anti-Spyware] "C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe" /minimized
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [ehTray.exe] C:\Windows\ehome\ehTray.exe
O4 - HKCU\..\Run: [AWMON] "C:\Program Files\Lavasoft\Ad-Aware SE Professional\Ad-Watch.exe"
O4 - HKCU\..\Run: [Tok-Cirrhatus] "C:\Users\admin\AppData\Local\smss.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')
O8 - Extra context menu item: E&xportar a Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Quick-Launching Area - {10954C80-4F0F-11d3-B17C-00C0DFE39736} - C:\Program Files\Acer\Acer Bio-Protection fingerprint solution\PwdBank.exe
O9 - Extra 'Tools' menuitem: Quick-Launching Area - {10954C80-4F0F-11d3-B17C-00C0DFE39736} - C:\Program Files\Acer\Acer Bio-Protection fingerprint solution\PwdBank.exe
O9 - Extra button: (no name) - {9034A523-D068-4BE8-A284-9DF278BE776E} - http://www.topsoftwarefeed.com/redirect.php (file missing)
O9 - Extra 'Tools' menuitem: IE Anti-Spyware - {9034A523-D068-4BE8-A284-9DF278BE776E} - http://www.topsoftwarefeed.com/redirect.php (file missing)
O9 - Extra button: Referencia - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.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
O16 - DPF: {0EB0E74A-2A76-4AB3-A7FB-9BD8C29F7F75} (CKAVWebScan Object) - http://www.kaspersky.com/kos/spanish//kavwebscan_unicode.cab
O16 - DPF: {4A026B12-94F3-4D2F-A468-96AA55DE20A5} (NetCamPlayerWeb11g Control) - http://cotlamani3.ourlinksys.com:1027/img/NetCamPlayerWeb11g.ocx
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O20 - Winlogon Notify: !SASWinLogon - C:\Program Files\SUPERAntiSpyware\SASWINLO.dll
O20 - Winlogon Notify: AWinNotifyVitaKey MC3000 - C:\Program Files\Acer\Acer Bio-Protection fingerprint solution\WinNotify.dll
O23 - Service: Agere Modem Call Progress Audio (AgereModemAudio) - Agere Systems - C:\Windows\system32\agrsmsvc.exe
O23 - Service: AVG Anti-Spyware Guard - GRISOFT s.r.o. - C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: AdminWorks Agent X6 (AWService) - OSA Technologies Inc., An Avocent Company - C:\Acer\Empowering Technology\awServ.exe
O23 - Service: lxbm_device - - C:\Windows\system32\lxbmcoms.exe
O23 - Service: NOD32 Kernel Service (NOD32krn) - Eset - C:\Program Files\Eset\nod32krn.exe
O23 - Service: SBSD Security Center Service (SBSDWSCService) - Safer Networking Ltd. - C:\Program Files\Spybot - Search & Destroy\SDWinSec.exe
O23 - Service: SuperProServer - Unknown owner - C:\Program Files\Rainbow Technologies\SPN Combo Installer\1.0.2\Server\WinNT\spnsrvnt.exe

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