Explorer.exe crashes systematically but annoyingly often

My explorer.exe began crashing yesterday, on at least these occasions:
Rightclick on an icon on desktop or in explorer-window
Deleting an icon (with delete-key)
Rightclicking on Start-button (not the taskbar itself)

It crashes every single time, with this message:

Microsoft Visual C++ Runtime Library
------------------------------------
Runtime Error!
Program: C:\WINDOWS\explorer.exe

abnormal program termination

------------------------------------

When I click the OK-button icons+taskbar vanishes and explorer restarts. Everything else seems to be working like usual...

I do not remember that I should have done anything weird or installed malicious software yesterday. I only use Firefox as a browser and I have Norton Antivirus 2005 running in the back...

I have run the guide: "Spyware, Trojan & Virus-removal" on Major Geeks, very thorougly, but with no luck. The various removers did however find a number of tracking cookies and spywares, plus Norton popped up twice with a 'removed a virus'-message during one of the scans.

During the removal-guide, I noticed that the error occured in Safe Mode with Networking as well...

Im running Windows XP, SP2 with the freshest updates from Windows Update. I have a AMD XP 2000+, 512 MB DDR ram and Radeon 9600 graphics.

About 30 minutes ago Norton popped up with this message:
---------------------------------
Rule "Default Block Bla Trojan horse" blocked
Inbound UDP packet.
Local address, service is (localhost, 1042)
Remote address, service is (T65(82.211.211.231),1042).
Process name is "N/A"
----------------------------------

Which to me looks like Im attacking myself with a trojan from an unknown process (???)... I noticed that netstat did not report port 1042 open, but about 10 ports from 1030-1040 open by the process 'cli.exe', which is a commandline-interface for ATI Control Centre. Funny that it needs that many ports... I do not know if this and the error is related...

Im pretty much at a loss, and if the situation doesnt improve I guess I have to reinstall or something...
Thanx for any help

 

There isnt anyone who has a suggestion to what the cause might be? Wether its spyware, virus or just ol' Windows gone havoc?

 

Do you get an error code or more information with your Visual C++ message?
Do you have any toolbars installed? or shell extensions installed (e.g., add-ons to the right-click menu)?
Do you see anything reported in your event log viewer?

 

Go to Start, Run and type in sfc /scannow (note there is a space after sfc )

You will need your Windows CD.

 

Is there anything of interest in the event viewer application error log? Any program that seems to be hanging constantly? Notice anything unusual about the system error log?

Event viewer: start-> run -> type "eventvwr.msc" without the quotes.

 

I tried the Windows File-scan, but it kept saying that my windows-cd was wrong... I'm pretty sure I know why, but not much to do there unfortunately...

I ran the Norton SystemWorks, but it didnt find anything severe...

Not much to see in the application-log, though the process to report the error was Winlogon. I guess its because Winlogon was the process to start explorer.exe...

Sure I have lots of shell-extensions. Most notably, I hacked the windows-theme-block so I could use non-Microsoft-themes. Also I have TortoiseSVN which puts a lot of icons in here and there. Otherwise I have Vim, WinRAR, Photoshop and lots of other programs that likes to put its grubby claws in my shell...

 

Oh yeah, and no errorcodes in the C++ message unfortunately.. Not much help there... In the evenviewer it says Event ID 1002 - dont know if that is connected with the process, the error or the event that triggered the error...
Der var et link til en artikel i Help and Support Center, men den var præcis så lidt informerende som de plejer at være. Linket var: http://go.microsoft.com/fwlink/events.asp
Der står bare at det er eventen EVENT_SHELL_RESTARTED, men siger intet om eventuel årsag...