F7 now opens Thunderbird and F8 opens Firefox. I don't know when this changed, but this overrides the functions for those keys in all programs (quick-save in games, insert date in my text editor).
The first thing I checked was mouse and keyboard drivers, but uninstalling them didn't change the behaviour.
I want to change the function keys back to their old behaviour.
Go to your Start menu and look for the shortcut for Mozilla Firefox. Right-click it and then at the bottom of the list select Properties. You should hopefully see something like this window:
Where my Shortcut Key says CTRL + ALT + SCROLL LOCK you can click in that box and press the backspace key to delete the shortcut.
If the key is not assigned to the shortcut on the start menu you may also need to look at the desktop icons.
