Arriving at my fishing spot, I put my Lowrance Hook 4 on
stand-by and proceeded to front of boat. I turned around
and saw my co-angler punching buttons on my LH4. He 
said he was trying to see the depth. When I went back, 
everything was gone! Settings, preferences and most
important.... all my waypoints and trails! The LH4 was
back to factory reset. My question, does anyone know
if I can recover my dozens of waypoints?     ..?

It's possible that with all the button punching the Hook 4 got put into a mode where it reads from some other map, chip set, or data set. I don't have mine handy right now but if I remember correctly it can be set to read data from one of several sources. Unless you very deliberately tell the unit to reset to factory defaults and erase the data, I think it's hard to lose all your waypoints and trails. Check the menus and try to convince the Hook 4 to read from your recorded data set, as opposed to some alternate / third party data set. If you get stuck, let me know and I'll throw mine on a battery and try to step you through it.

 

Hook 4 is a great unit especially with GPS. For short money it gives you all the basics without all the complication of a fancier unit. 

Thanks, I will explore the unit looking for this mode and get back to you.

If they are actually deleted then as far as I know they are gone.  Do you have another unit networked with it?

 

 

Make sure you're not in simulator mode ?

Talked to Lowrance tech. and was told that a certain sequence of buttons pushed will

completely remove all stored data including waypoints, trails etc. and there is no way

to recover them. Co-angler must have hit that sequence. Tech told me how I can back-up 

info with a SD chip as I will be doing from now on. (I was not aware this could be done)

Thanks for ideas.

...and this is why you never let a co-angler play with *your* electronics.

I did the same thing on my unit a couple of months ago; called Lowrance and was told they're gone forever.  Had to load my backup but lost the recent entries.  Backups are mandatory and if they're updated they're even better.