at.exe - application error

obligatory "I am incompetent at computers and this is my first time posting in a tech forum, please forgive any newbie screw-ups" warning. (:

Okay, so after maybe 30 minutes or so on my laptop I get a popup that says "at.exe - application error / The application failed to initialize properly (0xc0000142). Click on OK to terminate the application." Clicking the OK button at the bottom of the window does nothing, the pop-up just reappears immediately and stays put until I shut down the computer.

So far I've run Spybot S&D and rKill / MBAM scans until all results have come up clean; likewise with Kapersky's Wise Registry Cleaner and TDSSKiller.

Computer: Dell Inspiron I6400, Genuine Intel ® CPU, T2400 2 1.83 GHz, 987 MHz, 200.GB of RAM

System: Microsoft Windows XP Professional, Version 2002, Service Pack 2

Let me know if I'm missing any info that you need. Thanks in advance for your help and patience!

Hi hellkite.
I too am new to this so please would everyone be patient with me. I am a user but not a 'techie'.
I have had the same error message after a recent Malware incident.
As I understand it, at.exe is used by Windows to run scheduled tasks. A list of tasks can be accessed through :
start - control panel - scheduled tasks
I found several that I did not recognise, named 'at 1' - 'at x' (I think there were 10 or so). Deleting these tasks has made the problem go away: at least so far. I presume that these tasks were inserted with malicious intent but I did not investigate further to see what they were trying to do.
Best of luck with your own problem.