When I click on the Firefox short cut or menu item from the Start menu of my PC nothing happens. When I check my Program Files there are still Firefox files in the correct folder, but the program is not opening. This has only happened in the last couple of days, it was fine up till then. What could have caused this? Should I simply remove Firefox from my PC using Add / Remove Programs and then re-install Firefox, or is there something else I can do, to keep my bookmarks etc? Thanks!