I have Avast 4.8 Home Edition!
And i have the Automatic Update ON:
However when i on the PC i get a msg at the system tray that my Avast is not up2 date.
So i did the Update Manually. And i still get that msg!
This is the Msg.
""avast! antivirus 4.8.1201 [VPS 080628-0] might be out of date""
I did a scan with Malwarebytes' Anti-Malware and that didnt find anything. And also i did a scan with Spybot - Search & Destroy that found this "Microsoft.WindowsSecurityCenter.AntiVirusOverride", and i deleted that.
And still the msg comes up! so Here is a Hijack Log. **When i scan again after 5hrs with Spybot - Search & Destroy the "Microsoft.WindowsSecurityCenter.AntiVirusOverride" still shows up.

Thank-You!
--------------------
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 9:55:57 PM, on 28/07/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.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:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\Program Files\Bonjour\mDNSResponder.exe
C:\WINDOWS\system32\crypserv.exe
C:\Program Files\Analog Devices\SoundMAX\SMAgent.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Analog Devices\SoundMAX\SMax4PNP.exe
C:\Program Files\Analog Devices\SoundMAX\Smax4.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\Microsoft IntelliType Pro\type32.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Windows Live\installer\WLSetupSvc.exe
C:\Program Files\Windows Live\Messenger\msnmsgr.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Common Files\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Program Files\Spybot - Search & Destroy\SpybotSD.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

O2 - BHO: Adobe PDF Reader Link Helper - {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: Groove GFS Browser Helper - {72853161-30C5-4D22-B7F9-0BBC1D38A37E} - C:\PROGRA~1\MICROS~2\Office12\GRA8E1~1.DLL
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O4 - HKLM\..\Run: [SoundMAXPnP] C:\Program Files\Analog Devices\SoundMAX\SMax4PNP.exe
O4 - HKLM\..\Run: [SoundMAX] "C:\Program Files\Analog Devices\SoundMAX\Smax4.exe" /tray
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [type32] "C:\Program Files\Microsoft IntelliType Pro\type32.exe"
O4 - HKLM\..\Run: [Adobe_ID0EYTHM] C:\PROGRA~1\COMMON~1\Adobe\ADOBEV~1\Server\bin\VER SIO~2.EXE
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'NETWORK SERVICE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [RunNarrator] Narrator.exe (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [RunNarrator] Narrator.exe (User 'Default user')
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra button: Send to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: S&end to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\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
O18 - Protocol: grooveLocalGWS - {88FED34C-F0CA-4636-A375-3CB6248B04CD} - C:\PROGRA~1\MICROS~2\Office12\GR99D3~1.DLL
O23 - Service: Ad-Aware 2007 Service (aawservice) - Lavasoft - C:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
O23 - Service: Adobe Version Cue CS3 - Adobe Systems Incorporated - C:\Program Files\Common Files\Adobe\Adobe Version Cue CS3\Server\bin\VersionCueCS3.exe
O23 - Service: Apple Mobile Device - Apple, Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: Ares Chatroom server (AresChatServer) - Ares Development Group - C:\Program Files\Ares\chatServer.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: ##Id_String1.6844F930_1628_4223_B5CC_5BB94B879762# # (Bonjour Service) - Apple Computer, Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: Crypkey License - CrypKey (Canada) Ltd. - C:\WINDOWS\SYSTEM32\crypserv.exe
O23 - Service: FLEXnet Licensing Service - Macrovision Europe Ltd. - C:\Program Files\Common Files\Macrovision Shared\FLEXnet Publisher\FNPLicensingService.exe
O23 - Service: iPod Service - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: SoundMAX Agent Service (SoundMAX Agent Service (default)) - Analog Devices, Inc. - C:\Program Files\Analog Devices\SoundMAX\SMAgent.exe

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End of file - 6484 bytes

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http://forum.avast.com/index.php?topic=35537.0