(This item pertains to the Probe Utilities dialog box, accessible through Insert | Hardware Definition | Probe.)
The Global Used command button is in the Probe Utilities dialog box.
The Global Used button searches for tips used in other measurement routines by the currently-active probe file. It then adds them to the Active tip list and marks them for calibration.
By default, this button searches through any measurement routine subdirectories. You can control whether or not this button searches these subdirectories by using the Include subdirectories in global used search check box in the Probe Setup dialog box.