having trouble getting rid of a trojan

[pbstac]

I need help! I have a Trojan(s) that I can't get rid of.

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 4:57:12 PM, on 10/3/2007
Platform: Windows XP SP1 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP1 (6.00.2800.1106)
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:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\System32\aniServ.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\iTunes\iTunesHelper.exe
C:\Program Files\Messenger\msmsgs.exe
C:\WINDOWS\System32\devldr32.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe
C:\WINDOWS\System32\wuauclt.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://us.rd.yahoo.com/customize/ie/defaul...rch/search.html
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://us.rd.yahoo.com/customize/ie/defaul...//www.yahoo.com
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.yahoo.com/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://us.rd.yahoo.com/customize/ie/defaul...//www.yahoo.com
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
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://us.rd.yahoo.com/customize/ie/defaul...//www.yahoo.com
F2 - REG:system.ini: UserInit=C:\WINDOWS\System32\Userinit.exe
O2 - BHO: (no name) - {6DBBE182-D82D-44B7-B9B2-841E2284CE92} - c:\windows\system32\dhcpcsvcp.dll
O2 - BHO: (no name) - {C7CFFA45-57D6-4B86-BAF2-EAF8BC6434B1} - C:\WINDOWS\System32\dpserialt.dll
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\msmsgs.exe" /background
O16 - DPF: {17492023-C23A-453E-A040-C7C580BBF700} (Windows Genuine Advantage Validation Tool) - http://go.microsoft.com/fwlink/?linkid=39204
O20 - Winlogon Notify: yuojztok - C:\WINDOWS\SYSTEM32\dhcpcsvcp.dll
O23 - Service: Airgo Networks NIC Service (ANISERVICE) - Airgo Networks, Inc. - C:\WINDOWS\System32\aniServ.exe
O23 - Service: iPod Service - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe

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End of file - 2739 bytes

[guestolo]

I see a lack of Windows updates and no Antivirus software installed on this computer

Try the following
Download Dr.Web CureIt to the desktop from this link
ftp://ftp.drweb.com/pub/drweb/cureit/drweb-cureit.exe

Double click to run Dr.Web-cureit.exe from desktop

• Allow to run the express scan
• This will scan the files currently running in memory and when something is found, click the yes button when it asks you if you want to cure it. This is only a short scan.
• Once the short scan has finished, Click Options > Change settings
  
• Choose the "Scan"-tab, remove the mark at "Heuristic analysis".
• Back at the main window, mark the drives that you want to scan.
• Select all drives. A red dot shows which drives have been chosen.
• Click the green arrow at the right, and the scan will start.
  
• Click 'Yes to all' if it asks if you want to cure/move the file.
• When the scan has finished, look if you can click next icon next to the files found:
  
• If so, click it and then click the next icon right below and select Move incurable as you'll see in next image:
  
  This will move it to the %userprofile%\DoctorWeb\quarantaine-folder if it can't be cured.
  
• After selecting, in the Dr.Web CureIt menu on top, click file and choose save report list
  
• Save the report to your desktop. The report will be called DrWeb.csv
  
• Close Dr.Web Cureit.
• Reboot your computer

Post the report from Dr. Web and a fresh hijackthis log