How to reset Forerunner 405?
How To Reset Garmin Forerunner 405
Soft reset (does not erase any stored data): press and hold simultaneously (for about 7 sec)? the only two silver buttons on your FR: “enter” and “quit” until the screen goes blank.
Hard reset (will clear all the user data): the same like above, press and hold “enter” and “quit” buttons simulatenously for about 7 sec, until the screen goes balnk. Then release the “enter” button, but keep holding the “quit” button for about 3 sec and release. After that a csreen will pop up asking if you wish to erase the data: to confirm press “enter”, if you decide no to do it, press “quit”.