I have strange problem on my HP laptop. This began to happen recently. Whenever I start my machine, Windows 7 Action Center displays the following warning:

You need to restart your computer for UAC to be turned off.

Actually, this does not happen if it happened once on a specific day. For example, when I start the machine in the morning, it shows up; but it never shows up in the subsequent restarts within that day. On the next day, the same thing happens again.

I never disable UAC, but obviously some rootkit or virus causes this. As soon as I get this warning, I head for the UAC settings, and re-enable UAC to dismiss this warning. This is a bothersome situation as I can't fix it.

First, I have run a full scan on the computer for any probable virus and malware/rootkit activity, but TrendMicro OfficeScan said that no viruses have been found. I went to an old Restore Point using Windows System Restore, but the problem was not solved.

What I have tried so far (which couldn't find the rootkit):

• TrendMicro OfficeScan Antivirus
• AVAST
• Malwarebytes' Anti-malware
• Ad-Aware
• Vipre Antivirus
• GMER
• TDSSKiller (Kaspersky Labs)
• HiJackThis
• RegRuns
• UnHackMe
• SuperAntiSpyware Portable
• Tizer Rootkit Razor (*)
• Sophos Anti-Rootkit
• SpyHunter 4

There are no other strange activities on the machine. Everything works fine except this bizarre incident.

What could be the name of this annoying rootkit? How can I detect and remove it?

EDIT: Below is the log file generated by HijackThis:

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 13:07:04, on 17.01.2011
Platform: Windows 7  (WinNT 6.00.3504)
MSIE: Internet Explorer v8.00 (8.00.7600.16700)
Boot mode: Normal

Running processes:
C:\Windows\system32\taskhost.exe
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Program Files\CheckPoint\SecuRemote\bin\SR_GUI.Exe
C:\Windows\System32\igfxtray.exe
C:\Windows\System32\hkcmd.exe
C:\Windows\system32\igfxsrvc.exe
C:\Windows\System32\igfxpers.exe
C:\Program Files\Hewlett-Packard\HP Wireless Assistant\HPWAMain.exe
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\QLBCTRL.exe
C:\Program Files\Analog Devices\Core\smax4pnp.exe
C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\VolCtrl.exe
C:\Program Files\LightningFAX\LFclient\lfsndmng.exe
C:\Program Files\Common Files\Java\Java Update\jusched.exe
C:\Program Files\Microsoft Office Communicator\communicator.exe
C:\Program Files\Iron Mountain\Connected BackupPC\Agent.exe
C:\Program Files\Trend Micro\OfficeScan Client\PccNTMon.exe
C:\Program Files\Microsoft LifeCam\LifeExp.exe
C:\Program Files\Hewlett-Packard\Shared\HpqToaster.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\mimio\mimio Studio\system\aps_tablet\atwtusb.exe
C:\Program Files\Microsoft Office\Office12\OUTLOOK.EXE
C:\Program Files\Babylon\Babylon-Pro\Babylon.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Users\userx\Desktop\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,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 = 
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,AutoConfigURL = http://www.yaysat.com.tr/proxy/proxy.pac
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = 
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: Babylon IE plugin - {9CFACCB6-2F3F-4177-94EA-0D2B72D384C1} - C:\Program Files\Babylon\Babylon-Pro\Utils\BabylonIEPI.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files\Java\jre6\bin\jp2ssv.dll
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: [hpWirelessAssistant] C:\Program Files\Hewlett-Packard\HP Wireless Assistant\HPWAMain.exe
O4 - HKLM\..\Run: [SynTPEnh] C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
O4 - HKLM\..\Run: [QlbCtrl.exe] C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\QlbCtrl.exe /Start
O4 - HKLM\..\Run: [SoundMAXPnP] C:\Program Files\Analog Devices\Core\smax4pnp.exe
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 9.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [Adobe ARM] "C:\Program Files\Common Files\Adobe\ARM\1.0\AdobeARM.exe"
O4 - HKLM\..\Run: [lfsndmng] C:\Program Files\LightningFAX\LFclient\LFSNDMNG.EXE
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Common Files\Java\Java Update\jusched.exe"
O4 - HKLM\..\Run: [Communicator] "C:\Program Files\Microsoft Office Communicator\communicator.exe" /fromrunkey
O4 - HKLM\..\Run: [AgentUiRunKey] "C:\Program Files\Iron Mountain\Connected BackupPC\Agent.exe" -ni -sss -e http://localhost:16386/
O4 - HKLM\..\Run: [OfficeScanNT Monitor] "C:\Program Files\Trend Micro\OfficeScan Client\pccntmon.exe" -HideWindow
O4 - HKLM\..\Run: [Babylon Client] C:\Program Files\Babylon\Babylon-Pro\Babylon.exe -AutoStart
O4 - HKLM\..\Run: [LifeCam] "C:\Program Files\Microsoft LifeCam\LifeExp.exe"
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - Global Startup: mimio Studio.lnk = C:\Program Files\mimio\mimio Studio\mimiosys.exe
O8 - Extra context menu item: Microsoft Excel'e &Ver - res://C:\PROGRA~1\MICROS~1\Office12\EXCEL.EXE/3000
O8 - Extra context menu item: Translate this web page with Babylon - res://C:\Program Files\Babylon\Babylon-Pro\Utils\BabylonIEPI.dll/ActionTU.htm
O8 - Extra context menu item: Translate with Babylon - res://C:\Program Files\Babylon\Babylon-Pro\Utils\BabylonIEPI.dll/Action.htm
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~1\Office12\REFIEBAR.DLL
O9 - Extra button: Translate this web page with Babylon - {F72841F0-4EF1-4df5-BCE5-B3AC8ACF5478} - C:\Program Files\Babylon\Babylon-Pro\Utils\BabylonIEPI.dll
O9 - Extra 'Tools' menuitem: Translate this web page with Babylon - {F72841F0-4EF1-4df5-BCE5-B3AC8ACF5478} - C:\Program Files\Babylon\Babylon-Pro\Utils\BabylonIEPI.dll
O16 - DPF: {00134F72-5284-44F7-95A8-52A619F70751} (ObjWinNTCheck Class) - https://172.20.12.103:4343/officescan/console/html/ClientInstall/WinNTChk.cab
O16 - DPF: {08D75BC1-D2B5-11D1-88FC-0080C859833B} (OfficeScan Corp Edition Web-Deployment SetupCtrl Class) - https://172.20.12.103:4343/officescan/console/html/ClientInstall/setup.cab
O17 - HKLM\System\CCS\Services\Tcpip\Parameters: Domain = yaysat.com
O17 - HKLM\Software\..\Telephony: DomainName = yaysat.com
O17 - HKLM\System\CS1\Services\Tcpip\Parameters: Domain = yaysat.com
O17 - HKLM\System\CS2\Services\Tcpip\Parameters: Domain = yaysat.com
O18 - Protocol: qcom - {B8DBD265-42C3-43E6-B439-E968C71984C6} - C:\Program Files\Common Files\Quest Shared\CodeXpert\qcom.dll
O22 - SharedTaskScheduler: FencesShellExt - {1984DD45-52CF-49cd-AB77-18F378FEA264} - C:\Program Files\Stardock\Fences\FencesMenu.dll
O23 - Service: Andrea ADI Filters Service (AEADIFilters) - Andrea Electronics Corporation - C:\Windows\system32\AEADISRV.EXE
O23 - Service: AgentService - Iron Mountain Incorporated - C:\Program Files\Iron Mountain\Connected BackupPC\AgentService.exe
O23 - Service: Agere Modem Call Progress Audio (AgereModemAudio) - LSI Corporation - C:\Program Files\LSI SoftModem\agrsmsvc.exe
O23 - Service: BMFMySQL - Unknown owner - C:\Program Files\Quest Software\Benchmark Factory for Databases\Repository\MySQL\bin\mysqld-max-nt.exe
O23 - Service: Com4QLBEx - Hewlett-Packard Development Company, L.P. - C:\Program Files\Hewlett-Packard\HP Quick Launch Buttons\Com4QLBEx.exe
O23 - Service: hpqwmiex - Hewlett-Packard Development Company, L.P. - C:\Program Files\Hewlett-Packard\Shared\hpqwmiex.exe
O23 - Service: OfficeScanNT RealTime Scan (ntrtscan) - Trend Micro Inc. - C:\Program Files\Trend Micro\OfficeScan Client\ntrtscan.exe
O23 - Service: SMS Task Sequence Agent (smstsmgr) - Unknown owner - C:\Windows\system32\CCM\TSManager.exe
O23 - Service: Check Point VPN-1 Securemote service (SR_Service) - Check Point Software Technologies - C:\Program Files\CheckPoint\SecuRemote\bin\SR_Service.exe
O23 - Service: Check Point VPN-1 Securemote watchdog (SR_Watchdog) - Check Point Software Technologies - C:\Program Files\CheckPoint\SecuRemote\bin\SR_Watchdog.exe
O23 - Service: Trend Micro Unauthorized Change Prevention Service (TMBMServer) - Trend Micro Inc. - C:\Program Files\Trend Micro\OfficeScan Client\..\BM\TMBMSRV.exe
O23 - Service: OfficeScan NT Listener (tmlisten) - Trend Micro Inc. - C:\Program Files\Trend Micro\OfficeScan Client\tmlisten.exe
O23 - Service: OfficeScan NT Proxy Service (TmProxy) - Trend Micro Inc. - C:\Program Files\Trend Micro\OfficeScan Client\TmProxy.exe
O23 - Service: VNC Server Version 4 (WinVNC4) - RealVNC Ltd. - C:\Program Files\RealVNC\VNC4\WinVNC4.exe

--
End of file - 8204 bytes

As suggested in this very similar question, I have run full scans (+boot time scans) with RegRun and UnHackMe, but they also did not find anything. I have carefully examined all entries in the Event Viewer, but there's nothing wrong.

Now I know that there is a hidden trojan (rootkit) on my machine which seems to disguise itself quite successfully. Note that I don't have the chance to remove the HDD, or reinstall the OS as this is a work machine subjected to certain IT policies on a company domain.

Despite all my attempts, the problem still remains. I strictly need a to-the-point method or a pukka rootkit remover to remove whatever it is. I don't want to monkey with the system settings, i.e. disabling auto runs one by one, messing the registry, etc.

EDIT 2: I have found an article which is closely related to my trouble:

Malware can turn off UAC in Windows 7; “By design” says Microsoft. Special thanks(!) to Microsoft.

In the article, a VBScript code is given to disable UAC automatically:

'// 1337H4x Written by _____________ 
'//                    (12 year old)

Set WshShell = WScript.CreateObject("WScript.Shell")

'// Toggle Start menu
WshShell.SendKeys("^{ESC}")
WScript.Sleep(500)

'// Search for UAC applet
WshShell.SendKeys("change uac")
WScript.Sleep(2000)

'// Open the applet (assuming second result)
WshShell.SendKeys("{DOWN}")
WshShell.SendKeys("{DOWN}")
WshShell.SendKeys("{ENTER}")
WScript.Sleep(2000)

'// Set UAC level to lowest (assuming out-of-box Default setting)
WshShell.SendKeys("{TAB}")
WshShell.SendKeys("{DOWN}")
WshShell.SendKeys("{DOWN}")
WshShell.SendKeys("{DOWN}")

'// Save our changes
WshShell.SendKeys("{TAB}")
WshShell.SendKeys("{ENTER}")

'// TODO: Add code to handle installation of rebound
'// process to continue exploitation, i.e. place something
'// evil in Startup folder

'// Reboot the system
'// WshShell.Run "shutdown /r /f"

Unfortunately, that doesn't tell me how I can get rid of this malicious code running on my system.

EDIT 3: Last night, I left the laptop open because of a running SQL task. When I came in the morning, I saw that UAC was turned off. So, I suspect that the problem is not related to startup. It is happening once a day for sure no matter if the machine is rebooted.