Shut down error message

Hi all, and excuse my bad english.
I am new here, even I am using Avast from almost four years without any problem till now.
Afther upgrade to ver. 4.8, I receive an error message, for two seconds no more just before the computer shuts down, without any other malfunction.
http://img230.imageshack.us/img230/2087/imgp56821ml0.jpg

I read a lot here, and on Microsoft released topics, also I run AVG Anti-Rootkit, and I didn’t found anything to solve the problem.
Afther uninstall Avast, the problem dissapear, and reappear of course again afther reinstall it. What does it mean? Can anyone help me?
My OS is Win XP sp 2.
Thanks in advance for your help.

Is there any useful information into Control Panel > Administrative Tools > Events, specially ‘Errors’? Is there the reason (error message) of this event?

No, I didn’t found anything.
Thanks for replay.

Well, at least, try to read anything in that two seconds that could be related to avast or help troubleshooting…

All I can do in that one or two seconds was to shot the screen with an fast camera. First time I even can’t read all that message.
Also, tried to found something errors listed on Adm tools > Events, at time when my comp. were shut down, and nothing every thing were fine.
I don’t know what else to check.

Nobody can help me here?
Nobody had a problem like this, even an developer of this program don’t know how to solve this?

Catas, the problem seem the lack of info… it’s difficult to troubleshoot what we can’t diagnose…