Close all (browser) windows & rescan with hijackthis. When the scan is finished place a check in the box to the left of the following entries & click 'fix checked' :

O3 - Toolbar: (no name) - {62999427-33FC-4baf-9C9C-BCE6BD127F08} - (no file)

Can you get me the full name of this folder please.
C:\PROGRA~1\COMMON~1\TEKNUM~1\update.exe

Cannot find bridge.dll in your log????

Hi, I've done as suggested, HJT log as below:
Logfile of HijackThis v1.97.7
Scan saved at 16:09:05, on 12/06/2004
Platform: Windows XP SP1 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP1 (6.00.2800.1106)

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:\Program Files\Common Files\Symantec Shared\ccEvtMgr.exe
C:\WINDOWS\system32\cisvc.exe
C:\Program Files\Norton AntiVirus\navapsvc.exe
C:\WINDOWS\System32\nvsvc32.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\ZoneLabs\vsmon.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Thomson\SpeedTouch USB\Dragdiag.exe
C:\Program Files\Common Files\Symantec Shared\ccApp.exe
C:\Program Files\Microsoft IntelliPoint\point32.exe
C:\Program Files\Microsoft IntelliType Pro\type32.exe
C:\Program Files\Zone Labs\ZoneAlarm\zlclient.exe
C:\Program Files\Hewlett-Packard\HP Share-to-Web\hpgs2wnd.exe
C:\PROGRA~1\HEWLET~1\HPSHAR~1\hpgs2wnf.exe
C:\WINDOWS\kdx\KHost.exe
C:\PROGRA~1\DAP\DAP.EXE
C:\Program Files\Roxio\Easy CD Creator 5\DirectCD\DirectCD.exe
C:\WINDOWS\System32\ctfmon.exe
C:\WINDOWS\System32\RUNDLL32.EXE
C:\Program Files\iISystem Wiper\SystemWiper.exe
C:\Program Files\SpeedTouch\Dr SpeedTouch\drst.exe
C:\Program Files\Hewlett-Packard\AiO\hp psc 700 series\Bin\hpobrt07.exe
C:\Program Files\Sony Handheld\HOTSYNC.EXE
C:\Program Files\Messenger\msmsgs.exe
C:\Program Files\Microsoft Office\Office\1033\msoffice.exe
C:\PROGRA~1\HEWLET~1\AiO\Shared\Bin\hpoevm07.exe
C:\WINDOWS\System32\hpoipm07.exe
C:\Program Files\Hewlett-Packard\AiO\Shared\bin\hpOSTS07.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\WINDOWS\system32\cidaemon.exe
E:\My Documents\Downloads\Software\HijackThis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.bbc.co.uk/
O2 - BHO: (no name) - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 6.0\Reader\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O2 - BHO: NAV Helper - {BDF3E430-B101-42AD-A544-FADC6B084872} - C:\Program Files\Norton AntiVirus\NavShExt.dll
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\System32\msdxm.ocx
O3 - Toolbar: Norton AntiVirus - {42CDD1BF-3FFB-4238-8AD1-7859DF00B1D6} - C:\Program Files\Norton AntiVirus\NavShExt.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O4 - HKLM\..\Run: [SpeedTouch USB Diagnostics] "C:\Program Files\Thomson\SpeedTouch USB\Dragdiag.exe" /icon
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\System32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [ccApp] "C:\Program Files\Common Files\Symantec Shared\ccApp.exe"
O4 - HKLM\..\Run: [ccRegVfy] "C:\Program Files\Common Files\Symantec Shared\ccRegVfy.exe"
O4 - HKLM\..\Run: [IntelliPoint] "C:\Program Files\Microsoft IntelliPoint\point32.exe"
O4 - HKLM\..\Run: [type32] "C:\Program Files\Microsoft IntelliType Pro\type32.exe"
O4 - HKLM\..\Run: [Zone Labs Client] "C:\Program Files\Zone Labs\ZoneAlarm\zlclient.exe"
O4 - HKLM\..\Run: [Share-to-Web Namespace Daemon] C:\Program Files\Hewlett-Packard\HP Share-to-Web\hpgs2wnd.exe
O4 - HKLM\..\Run: [kdx] C:\WINDOWS\kdx\KHost.exe
O4 - HKLM\..\Run: [DownloadAccelerator] C:\PROGRA~1\DAP\DAP.EXE /STARTUP
O4 - HKLM\..\Run: [AdaptecDirectCD] "C:\Program Files\Roxio\Easy CD Creator 5\DirectCD\DirectCD.exe"
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\ctfmon.exe
O4 - HKCU\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\System32\NVMCTRAY.DLL,NvTaskbarInit
O4 - HKCU\..\Run: [FreeRAM XP] "J:\software\Performance_Toolkit\FreeRAM XP Pro 1.4\FreeRAM XP Pro 1.40.exe" -win
O4 - HKCU\..\Run: [iIWiper] C:\Program Files\iISystem Wiper\SystemWiper.exe m
O4 - HKCU\..\Run: [Update Service] C:\PROGRA~1\COMMON~1\TEKNUM~1\update.exe /startup
O4 - HKCU\..\Run: [STYLEXP] C:\Program Files\TGTSoft\StyleXP\StyleXP.exe -Hide
O4 - HKCU\..\Run: [STManager] "C:\Program Files\SpeedTouch\Dr SpeedTouch\drst.exe" -b
O4 - Startup: HotSync Manager.lnk = C:\Program Files\Sony Handheld\HOTSYNC.EXE
O4 - Global Startup: HPAiODevice(hp psc 700 series) - 1.lnk = C:\Program Files\Hewlett-Packard\AiO\hp psc 700 series\Bin\hpobrt07.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office\OSA9.EXE
O8 - Extra context menu item: &Download with &DAP - C:\PROGRA~1\DAP\dapextie.htm
O8 - Extra context menu item: &Google Search - res://c:\program files\google\GoogleToolbar2.dll/cmsearch.html
O8 - Extra context menu item: Backward &Links - res://c:\program files\google\GoogleToolbar2.dll/cmbacklinks.html
O8 - Extra context menu item: Cac&hed Snapshot of Page - res://c:\program files\google\GoogleToolbar2.dll/cmcache.html
O8 - Extra context menu item: Convert for CLIÉ - C:\Program Files\Sony\Image Converter\menu.htm
O8 - Extra context menu item: Download &all with DAP - C:\PROGRA~1\DAP\dapextie2.htm
O8 - Extra context menu item: Si&milar Pages - res://c:\program files\google\GoogleToolbar2.dll/cmsimilar.html
O8 - Extra context menu item: Translate into English - res://c:\program files\google\GoogleToolbar2.dll/cmtrans.html
O9 - Extra button: Researcher (HKLM)
O9 - Extra button: Messenger (HKLM)
O9 - Extra 'Tools' menuitem: Messenger (HKLM)
O12 - Plugin for .spop: C:\Program Files\Internet Explorer\Plugins\NPDocBox.dll
O16 - DPF: {02BCC737-B171-4746-94C9-0D8A0B2C0089} (Microsoft Office Template and Media Control) - http://office.microsoft.com/templates/ieawsdc.cab
O16 - DPF: {0E5F0222-96B9-11D3-8997-00104BD12D94} (PCPitstop Utility) - http://www.pcpitstop.com/pcpitstop/PCPitStop.CAB
O16 - DPF: {3E68E405-C6DE-49FF-83AE-41EE9F4C36CE} (Office Update Installation Engine) - http://office.microsoft.com/officeup...ntent/opuc.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://download.macromedia.com/pub/s...sh/swflash.cab
O16 - DPF: {F54C1137-5E34-4B95-95A5-BA56D4D8D743} (Secure Delivery) - http://www.gamespot.com/KDX22/download/kdx.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{A5747C6E-EC27-4F33-9324-31482052C263}: NameServer = 62.241.160.200 158.43.240.3

The teknum file is part of EasyCrypto, an encrypting programme. The folder name, as far as I can make out is C:\Program Files\Common Files\Teknum Systems\update.exe.

You say you can't find bridge.dll in my log - the error message I used to get (no more now, thanks) said the dll couldn't be found - am I just being dumb, or if it couldn't be found on startup, why should it be in the log?!
Thanks again for your help.

Because the log also consists of registry entries!

As caperjack said, the 04 entries in HJT relate to registry entries. When the actual file is deleted, the registry entry remains, leaving the system *looking* for it. Delete the reigistry entry with HJT & the error message goes too .