Garmin GNC 420 Pilot's Manual & Reference page 118

To delete all user waypoints from memory:
WPT PAGES
1. Select the user waypoint list, as described on page 108.
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2. Press to display an options window for the user waypoint list.
m
Deleting All
3. With "Delete All User Waypoints" highlighted, press .
User Waypoints E
4. A "delete all waypoints" confirmation window is displayed. With "Yes?" highlighted, press
E
to delete all user waypoints from memory.
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