I have accidentally deleted all my history in firefox and have been trying in vain to restore it using the folllowing method:-
I go to START > All programs > Accessories > System Tools > System Restore but when the date for which I want to retrieve the history is chosen in the calendar ( AND I HAVE TRIED IN VAIN SEVERAL DIFFERENT DATES) the end result is a message saying : "Your computer cannot be restored to that date".

My question: Why?

Many thks for any help and your patience with a 74-yr-old pensioner on a Medtierranean island.