Dialog box keyboard commands :

TAB: Move to the next control in the dialog box
• SHIFT+TAB: Move to the previous control in the dialog box


• SPACEBAR: If the current control is a button, this clicks the button. If the current control is a check box, this toggles the check box. If the current control is an option, this selects the option.
• ENTER: Equivalent to clicking the selected button (the button with the outline)
• ESC: Equivalent to clicking the Cancel button
• ALT+underlined letter in dialog box item: Move to the corresponding item