Ok, so I got a new bird a couple of months ago and have been working a lot on inputting waypoints. Some from time on the water, some from hot spots maps. I had about 65 of them on there...starting to build a nice library of fishing spots until I hit Format Nav Directories last night. That will clean your clock. I lost them all in one second. It didn't ask me yes or no...are you sure you want to do this. It just did it and it made me sad, mad and sick all at once!

Learning experience. I have already started the manual process of putting the hotspots back on it...and I've already backed them up on an SD card. Has anyone else had this experience? and if not, be careful with that selection!

Samething happened to me. 1168 waypoints down the tube but I did have them saved to Humminbird PC. I had no idea what format nav directories would do, but I do now.

This feature was requested to remove Nav Data when people sold their units so all GPS data was removed and it also removes corrupt data that can hinder the performance of the unit. It is always wise to save waypoints, routes and tracks prior.

I will pass on the idea to double check before deleting but it's just like doing a format on SD Card to clear the data.

WOW, that is good information to know. Thanks for sharing. I'm sure I would have made the same mistake at some point. They really need to give you a warning before proceeding with this function.

I was trying to change the format of the GPS coordinates when it happened and I guess that sounded like a logical choice to me. It would have been nice if it would have asked me, "Are you sure you want to delete all your waypoints?"

thanks Doug