A new user, IUSER_ADMIN, with administrator privileges keeps appearing on the Welcome Screen. I have logged on as Administrator and deleted the IUSER_ADMIN user (control userpasswords2) several times (in both safe mode and normal mode) but it always reappears after a few reboots.
Once McAfee reported that it detected a Trojan and that I should restart and scan. The scan showed no problems.
I ran SpyBot S&D and the problem persists.

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 8:35:59 AM, on 9/7/2008
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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Adobe\Photoshop Elements 5.0\PhotoshopElementsFileAgent.exe
C:\WINDOWS\ehome\ehtray.exe
C:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe
C:\WINDOWS\AGRSMMSG.exe
C:\Program Files\Java\jre1.6.0_03\bin\jusched.exe
C:\WINDOWS\system32\spool\drivers\w32x86\3\hpztsb12.exe
C:\Program Files\Amazon\Amazon Unbox Video\ADVWindowsClientService.exe
C:\Program Files\McAfee.com\Agent\mcagent.exe
C:\Program Files\ScanSoft\OmniPageSE4\OpwareSE4.exe
C:\Program Files\Adobe\Photoshop Elements 5.0\apdproxy.exe
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\Common Files\LogiShrd\LComMgr\Communications_Helper.exe
C:\Program Files\Logitech\QuickCam\Quickcam.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\WINDOWS\system32\ctfmon.exe
C:\WINDOWS\system32\afisicx.exe
C:\WINDOWS\eHome\ehRecvr.exe
C:\WINDOWS\eHome\ehSched.exe
c:\Program Files\Common Files\LightScribe\LSSrvc.exe
C:\Program Files\Common Files\LogiShrd\LVCOMSER\LVComSer.exe
C:\Program Files\Common Files\LogiShrd\LVMVFM\LVPrcSrv.exe
C:\WINDOWS\system32\mabidwe.exe
C:\WINDOWS\system32\macidwe.exe
C:\Program Files\McAfee\SiteAdvisor\McSACore.exe
C:\PROGRA~1\McAfee\MSC\mcmscsvc.exe
c:\program files\common files\mcafee\mna\mcnasvc.exe
c:\PROGRA~1\COMMON~1\mcafee\mcproxy\mcproxy.exe
C:\PROGRA~1\McAfee\VIRUSS~1\mcshield.exe
C:\Program Files\Common Files\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\Program Files\McAfee\MPF\MPFSrv.exe
C:\WINDOWS\system32\Nobicyt.exe
C:\WINDOWS\system32\noytcyr.exe
C:\WINDOWS\system32\perfs.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\system32\roytctm.exe
C:\WINDOWS\system32\sobicyt.exe
C:\WINDOWS\system32\sotpeca.exe
C:\WINDOWS\system32\soxpeca.exe
C:\cygwin\bin\cygrunsrv.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\tdxdowkc.exe
C:\cygwin\usr\sbin\sshd.exe
C:\WINDOWS\system32\tdydowkc.exe
C:\WINDOWS\system32\wsldoekd.exe
C:\Program Files\Common Files\LogiShrd\LVCOMSER\LVComSer.exe
C:\WINDOWS\system32\dllhost.exe
C:\WINDOWS\eHome\ehmsas.exe
C:\Program Files\Common Files\Logishrd\LQCVFX\COCIManager.exe
C:\WINDOWS\system32\wuauclt.exe
C:\PROGRA~1\McAfee\VIRUSS~1\mcsysmon.exe
C:\HP\KBD\KBD.EXE
C:\WINDOWS\ALCMTR.EXE
c:\windows\system\hpsysdrv.exe
C:\WINDOWS\system32\hphmon06.exe
C:\Program Files\Java\jre1.6.0_03\bin\jucheck.exe
c:\PROGRA~1\mcafee\msc\mcshell.exe
C:\PROGRA~1\McAfee\VIRUSS~1\mcods.exe
c:\PROGRA~1\mcafee\VIRUSS~1\mcvsshld.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://ie.redirect.hp.com/svs/rdr?TYPE=3&a;…&pf=desktop
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = http://us.rd.yahoo.com/customize/ie/defaul…rch/search.html
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://us.rd.yahoo.com/customize/ie/defaul…//www.yahoo.com
O1 - Hosts: 75.125.165.202 axexe.com
O1 - Hosts: 208.254.26.132 readersaccess.com
O1 - Hosts: 64.34.46.60 cashloansurvey.com
O1 - Hosts: 64.14.244.60 phoenixsites.com
O1 - Hosts: 208.254.26.132 growthcars.com
O1 - Hosts: 208.254.26.132 BuyersCondo.com
O2 - BHO: (no name) - {02478D38-C3F9-4efb-9B51-7695ECA05670} - (no file)
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: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O2 - BHO: scriptproxy - {7DB2D5A0-7241-4E79-B68D-6309F01C5231} - C:\Program Files\McAfee\VirusScan\scriptsn.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar1.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\3.1.807.1746\swg.dll
O2 - BHO: McAfee SiteAdvisor BHO - {B164E929-A1B6-4A06-B104-2CD0E90A88FF} - c:\PROGRA~1\mcafee\SITEAD~1\mcieplg.dll
O3 - Toolbar: HP view - {B2847E28-5D7D-4DEB-8B67-05D28BCF79F5} - c:\Program Files\HP\Digital Imaging\bin\HPDTLK02.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar1.dll
O3 - Toolbar: McAfee SiteAdvisor Toolbar - {0EBBBE48-BAD4-4B4C-8E5A-516ABECAE064} - c:\PROGRA~1\mcafee\SITEAD~1\mcieplg.dll
O4 - HKLM\..\Run: [ehTray] C:\WINDOWS\ehome\ehtray.exe
O4 - HKLM\..\Run: [HPBootOp] "C:\Program Files\Hewlett-Packard\HP Boot Optimizer\HPBootOp.exe" /run
O4 - HKLM\..\Run: [ATIPTA] C:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe
O4 - HKLM\..\Run: [LSBWatcher] c:\hp\drivers\hplsbwatcher\lsburnwatcher.exe
O4 - HKLM\..\Run: [AGRSMMSG] AGRSMMSG.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0_03\bin\jusched.exe"
O4 - HKLM\..\Run: [HPDJ Taskbar Utility] C:\WINDOWS\system32\spool\drivers\w32x86\3\hpztsb12.exe
O4 - HKLM\..\Run: [TkBellExe] "C:\Program Files\Common Files\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [mcagent_exe] C:\Program Files\McAfee.com\Agent\mcagent.exe /runkey
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [CanonSolutionMenu] C:\Program Files\Canon\SolutionMenu\CNSLMAIN.exe /logon
O4 - HKLM\..\Run: [SSBkgdUpdate] "C:\Program Files\Common Files\Scansoft Shared\SSBkgdUpdate\SSBkgdupdate.exe" -Embedding -boot
O4 - HKLM\..\Run: [OpwareSE4] "C:\Program Files\ScanSoft\OmniPageSE4\OpwareSE4.exe"
O4 - HKLM\..\Run: [Adobe Photo Downloader] "C:\Program Files\Adobe\Photoshop Elements 5.0\apdproxy.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [LogitechCommunicationsManager] "C:\Program Files\Common Files\LogiShrd\LComMgr\Communications_Helper.exe"
O4 - HKLM\..\Run: [LogitechQuickCamRibbon] "C:\Program Files\Logitech\QuickCam\Quickcam.exe" /hide
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-21-278098102-292333017-844449151-1009\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe (User 'chuck')
O4 - HKUS\S-1-5-21-278098102-292333017-844449151-1009\..\Run: [Yahoo! Pager] 1 (User 'chuck')
O4 - HKUS\S-1-5-21-278098102-292333017-844449151-1009\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe (User 'chuck')
O4 - HKUS\S-1-5-21-278098102-292333017-844449151-1009\..\Run: [Skype] "C:\Program Files\Skype\Phone\Skype.exe" /nosplash /minimized (User 'chuck')
O4 - HKUS\S-1-5-21-278098102-292333017-844449151-1011\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe (User 'Mark')
O4 - HKUS\S-1-5-21-278098102-292333017-844449151-1013\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe (User '?')
O4 - HKUS\S-1-5-21-278098102-292333017-844449151-501\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe (User 'Guest')
O4 - S-1-5-18 Startup: Logitech . Product Registration.lnk = C:\Program Files\Logitech\QuickCam\eReg.exe (User 'SYSTEM')
O4 - .DEFAULT Startup: Logitech . Product Registration.lnk = C:\Program Files\Logitech\QuickCam\eReg.exe (User 'Default user')
O4 - Startup: Logitech . Product Registration.lnk = C:\Program Files\Logitech\QuickCam\eReg.exe
O8 - Extra context menu item: &Google Search - res://C:\Program Files\Google\GoogleToolbar1.dll/cmsearch.html
O8 - Extra context menu item: Backward Links - res://C:\Program Files\Google\GoogleToolbar1.dll/cmbacklinks.html
O8 - Extra context menu item: Cached Snapshot of Page - res://C:\Program Files\Google\GoogleToolbar1.dll/cmcache.html
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MI1933~1\OFFICE11\EXCEL.EXE/3000
O8 - Extra context menu item: Similar Pages - res://C:\Program Files\Google\GoogleToolbar1.dll/cmsimilar.html
O8 - Extra context menu item: Translate into English - res://C:\Program Files\Google\GoogleToolbar1.dll/cmtrans.html
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MI1933~1\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
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O12 - Plugin for .spop: C:\Program Files\Internet Explorer\Plugins\NPDocBox.dll
O16 - DPF: {4ED9DDF0-7479-4BBE-9335-5A1EDB1D8A21} (McAfee.com Operating System Class) - http://download.mcafee.com/molbin/shared/m…90/mcinsctl.cab
O16 - DPF: {BB21F850-63F4-4EC9-BF9D-565BD30C9AE9} (ASquaredScanForm Element) - http://www.windowsecurity.com/trojanscan/axscan.cab
O16 - DPF: {BCC0FF27-31D9-4614-A68E-C18E1ADA4389} (DwnldGroupMgr Class) - http://download.mcafee.com/molbin/shared/m…,23/mcgdmgr.cab
O18 - Protocol: sacore - {5513F07E-936B-4E52-9B00-067394E91CC5} - c:\PROGRA~1\mcafee\SITEAD~1\mcieplg.dll
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\COMMON~1\Skype\SKYPE4~1.DLL
O23 - Service: Adobe Active File Monitor V5 (AdobeActiveFileMonitor5.0) - Unknown owner - C:\Program Files\Adobe\Photoshop Elements 5.0\PhotoshopElementsFileAgent.exe
O23 - Service: Amazon Unbox Video Service (ADVService) - Amazon.com - C:\Program Files\Amazon\Amazon Unbox Video\ADVWindowsClientService.exe
O23 - Service: afisicx Manages messages (afisicx) - Unknown owner - C:\WINDOWS\system32\afisicx.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: Imapi Helper - Alex Feinman - C:\Program Files\Alex Feinman\ISO Recorder\ImapiHelper.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Unknown owner - c:\Program Files\Common Files\LightScribe\LSSrvc.exe
O23 - Service: LVCOMSer - Logitech Inc. - C:\Program Files\Common Files\LogiShrd\LVCOMSER\LVComSer.exe
O23 - Service: Process Monitor (LVPrcSrv) - Logitech Inc. - C:\Program Files\Common Files\LogiShrd\LVMVFM\LVPrcSrv.exe
O23 - Service: mabidwe Service (mabidwe) - Unknown owner - C:\WINDOWS\system32\mabidwe.exe
O23 - Service: macidwe Service (macidwe) - Unknown owner - C:\WINDOWS\system32\macidwe.exe
O23 - Service: McAfee SiteAdvisor Service - Unknown owner - C:\Program Files\McAfee\SiteAdvisor\McSACore.exe
O23 - Service: McAfee Services (mcmscsvc) - McAfee, Inc. - C:\PROGRA~1\McAfee\MSC\mcmscsvc.exe
O23 - Service: McAfee Network Agent (McNASvc) - McAfee, Inc. - c:\program files\common files\mcafee\mna\mcnasvc.exe
O23 - Service: McAfee Scanner (McODS) - McAfee, Inc. - C:\PROGRA~1\McAfee\VIRUSS~1\mcods.exe
O23 - Service: McAfee Proxy Service (McProxy) - McAfee, Inc. - c:\PROGRA~1\COMMON~1\mcafee\mcproxy\mcproxy.exe
O23 - Service: McAfee Real-time Scanner (McShield) - McAfee, Inc. - C:\PROGRA~1\McAfee\VIRUSS~1\mcshield.exe
O23 - Service: McAfee SystemGuards (McSysmon) - McAfee, Inc. - C:\PROGRA~1\McAfee\VIRUSS~1\mcsysmon.exe
O23 - Service: McAfee Personal Firewall Service (MpfService) - McAfee, Inc. - C:\Program Files\McAfee\MPF\MPFSrv.exe
O23 - Service: NOBICYT - Unknown owner - C:\WINDOWS\system32\Nobicyt.exe
O23 - Service: noytcyr Service (noytcyr) - Unknown owner - C:\WINDOWS\system32\noytcyr.exe
O23 - Service: perfmons - Unknown owner - C:\WINDOWS\system32\perfs.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: SonicWall VPN Client Service (RampartSvc) - SonicWALL, Inc. - C:\Program Files\SonicWALL\SonicWALL Global VPN Client\RampartSvc.exe
O23 - Service: routing Service (routing) - Unknown owner - C:\WINDOWS\system32\routing.exe (file missing)
O23 - Service: roytctm Service (roytctm) - Unknown owner - C:\WINDOWS\system32\roytctm.exe
O23 - Service: sobicyt - Unknown owner - C:\WINDOWS\system32\sobicyt.exe
O23 - Service: sotpeca Manages messages (sotpeca) - Unknown owner - C:\WINDOWS\system32\sotpeca.exe
O23 - Service: soxpeca Service (soxpeca) - Unknown owner - C:\WINDOWS\system32\soxpeca.exe
O23 - Service: CYGWIN sshd (sshd) - Unknown owner - C:\cygwin\bin\cygrunsrv.exe
O23 - Service: tdxdowkc Service (tdxdowkc) - Unknown owner - C:\WINDOWS\system32\tdxdowkc.exe
O23 - Service: tdydowkc Service (tdydowkc) - Unknown owner - C:\WINDOWS\system32\tdydowkc.exe
O23 - Service: wsldoekd Corporation (wsldoekd) - Unknown owner - C:\WINDOWS\system32\wsldoekd.exe

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