So she should either disable whatever hot key processing application she is running, or go into its settings and disable the one that starts the email application. Or kill the Office Sidebar maybe?
Actually, that might work. If the full software package is installed for the keyboard (not just the generic Windows driver), there is usually an option there to change or disable hotkeys. If the mail key is disabled, theoretically it should ignore that signal, regardless of it comes from the hotkey itself of through this malfunction. The keyboard doesn't know the difference, which is why it's doing it in the first place. If the caps lock is still doing what it should do (toggling caps)
and triggering the mail program, telling the keyboard to disable the mail shortcut should make it only toggle the caps again. It will of course still be sending out that mail signal, but it should be harmlessly ignored.
Mrs. J, have you installed the software package that comes with that keyboard? If not, you might try that. If you lost the CD, look on the bottom of the keyboard for the name and model of that keyboard. The software should be available through Logitech.
