Hey agb, you might want to give some more information. Like how long has the problem been occuring, is it a new computer, or did you change something on your system, or did it just start happening randomly? Have you got IE 7?
And if it's not working I'm not sure how u're getting access to the internet, but you might want to try downloading Firefox from here
and see if you still get the problem.
Also if you recently changed hardware, undo the change and see if it helps. If you recently changed software, use System Restore, that might help. Don't know what other people reckon really. Also try Microsoft's Support Forums/Articles, I've gotten some good help from there many a time.
the problem started about six months ago i have tried to find a solution ever since , it doesnt stop any applications it just pops up, i have IE7, and xp home edition , at its worst it will require me to restart explorer.exe from the task manager, i keep the pc pretty clean defrag , scan disc , spyware and adware cleaners etc its more of a nuiscence than anything tried system restore and havnt got any new hardware