xlEnableCancelKey

Specifies how Microsoft Excel handles Ctrl + Break (or Esc or Command + Period) user interruptions to the running procedure.

xlDisabled	All the keystrokes are ignored and trapping is disabled (0)
xlErrorHandler	The keystroke is sent to the running procedure as an error that is trappable by an error handler using the On Error GoTo statement This error code is 18 (2)
xlInterrupt*	Allows you to interrupt the macro by pressing (Ctrl + Break) (1)

xlDisabled

All the keystrokes are ignored and trapping is disabled (0)

xlErrorHandler

The keystroke is sent to the running procedure as an error that is trappable by an error handler using the On Error GoTo statement
This error code is 18 (2)

xlInterrupt*

Allows you to interrupt the macro by pressing (Ctrl + Break) (1)