If no luck, you might have a DNS hijacker or other malware blocking Windows Updates.
Please click here to download and install version 2.0.2 of the HijackThis Installer.
Run it and select Do a system scan and save a logfile.
The log will be saved in Notepad. Copy and paste the log in your next post.
Do not fix anything
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 10:55:27 AM, on 5/5/2010
Platform: Windows Vista (WinNT 6.00.1904)
MSIE: Internet Explorer v8.00 (8.00.6001.18904)
Boot mode: Normal
Running processes:
C:\Program Files\Norton AntiVirus\Engine\17.6.0.32\ccSvcHst.exe
C:\Windows\system32\taskeng.exe
C:\Windows\SYSTEM32\WISPTIS.EXE
C:\Windows\Explorer.EXE
C:\Windows\system32\Dwm.exe
C:\Windows\WindowsMobile\wmdc.exe
C:\Program Files\Qwest Personal Digital Vault\QwestPersonalDigitalVault.exe
C:\Windows\ehome\ehtray.exe
C:\Program Files\McAfee Security Scan\2.0.181\SSScheduler.exe
C:\Windows\System32\mobsync.exe
C:\Program Files\UltraMon\UltraMon.exe
C:\Program Files\UltraMon\UltraMonTaskbar.exe
C:\Windows\ehome\ehmsas.exe
C:\Windows\system32\wuauclt.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Windows\system32\SearchFilterHost.exe
C:\Program Files\UltraMon\UltraMonUiAcc.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL =
http://qwest.live.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 = 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,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\Main,Local Page =
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Local Page =
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Windows Internet Explorer provided by Qwest
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
R3 - URLSearchHook: ToolbarURLSearchHook Class - {CA3EB689-8F09-4026-AA10-B9534C691CE0} - C:\Program Files\Search Toolbar\tbhelper.dll
O1 - Hosts: ::1 localhost
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: Symantec Intrusion Prevention - {6D53EC84-6AAE-4787-AEEE-F4628F01010C} - C:\Program Files\Norton AntiVirus\Engine\17.6.0.32\IPSBHO.DLL
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files\Java\jre6\bin\jp2ssv.dll
O2 - BHO: TBSB05974 - {FCBCCB87-9224-4B8D-B117-F56D924BEB18} - C:\Program Files\Search Toolbar\tbcore3.dll
O3 - Toolbar: Search Toolbar - {0C8413C1-FAD1-446C-8584-BE50576F863E} - C:\Program Files\Search Toolbar\tbcore3.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [Windows Mobile Device Center] %windir%\WindowsMobile\wmdc.exe
O4 - HKLM\..\Run: [Qwest Personal Digital Vault] "C:\Program Files\Qwest Personal Digital Vault\QwestPersonalDigitalVault.exe" /m
O4 - HKCU\..\Run: [ehTray.exe] C:\Windows\ehome\ehTray.exe
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'NETWORK SERVICE')
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: McAfee Security Scan Plus.lnk = ?
O4 - Global Startup: UltraMon.lnk = ?
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~3\Office12\EXCEL.EXE/3000
O9 - Extra button: @C:\Windows\WindowsMobile\INetRepl.dll,-222 - {2EAF5BB1-070F-11D3-9307-00C04FAE2D4F} - C:\Windows\WindowsMobile\INetRepl.dll
O9 - Extra button: (no name) - {2EAF5BB2-070F-11D3-9307-00C04FAE2D4F} - C:\Windows\WindowsMobile\INetRepl.dll
O9 - Extra 'Tools' menuitem: @C:\Windows\WindowsMobile\INetRepl.dll,-223 - {2EAF5BB2-070F-11D3-9307-00C04FAE2D4F} - C:\Windows\WindowsMobile\INetRepl.dll
O13 - Gopher Prefix:
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) -
http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\AppleMobileDeviceService.exe
O23 - Service: Bonjour Service - Apple Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: iPod Service - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: Process Monitor (LVPrcSrv) - Logitech Inc. - C:\Program Files\Common Files\LogiShrd\LVMVFM\LVPrcSrv.exe
O23 - Service: McAfee Security Scan Component Host Service (McComponentHostService) - McAfee, Inc. - C:\Program Files\McAfee Security Scan\2.0.181\McCHSvc.exe
O23 - Service: Norton AntiVirus (NAV) - Symantec Corporation - C:\Program Files\Norton AntiVirus\Engine\17.6.0.32\ccSvcHst.exe
O23 - Service: NVIDIA Display Driver Service (nvsvc) - NVIDIA Corporation - C:\Windows\system32\nvvsvc.exe
O23 - Service: SupportSoft RemoteAssist - SupportSoft, Inc. - C:\Program Files\Common Files\SupportSoft\bin\ssrc.exe
O23 - Service: Stardock WindowBlinds (WindowBlinds) - Stardock Corporation - C:\PROGRA~1\Stardock\OBJECT~1\WINDOW~1\VistaSrv.exe
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End of file - 6086 bytes