ctrl+alt+del

The ctrl+alt+del function on my windows XP machine has been disabled, How do
I get this funtion enabled again.

This was a problem I had and although I tried all of the resolutions posted
on this site, none of them worked. The only way I could get the ctrl+alt+del
function working again was to roll my computer back to the earliest date
available to me, this seems to work only if I activate the function whilst
the computer is loading the task bar, If I do this then I can turn
ctrl+alt+del off after all the tasks on the control bar have been created,
this then allows me to use this function any time.

I would like to thank all the people for there surgestions in trying to
solve this problem.