First thing I'd do is download SeaClear or another one of the freebie software and see if you can get it working there. For importing waypoints into SeaClear, there are definitely people in here that can help. Search this forum for the SeaClear thread(s).
If that doesn't help you come up with a solution, I would look for forums
on the GPS
and/or chart software the waypoints came from (and/or headed to). Every system behaves very different.
Case in point: I use Nobeltec
. But as a backup, I always load the raw routes on to my standalone Garmin GPS
. To get routes from Nobeltec
into my Garmin
, I set the GPS communications
and export the waypoints and routes from Nobeltec to my GPS. But the waypoints and routes are named sequentially, and there's no way I can fix it. So, I set the GPS back to Garmin mode and download the routes from the GPS to Garmin's MapSource software, rename the routes and waypoints (usually according to the Intracoastal or river mile markers), delete the old routes from the GPS, then load the renamed version back up to the GPS. This convoluted method is needed because there is no way I know to get the routes and waypoints from Nobeltec to MapSource. (As an aside: It sounds convoluted, but I've done it so often, I can be a mile from the next waypoint, have the mate steer a compass
heading to it, grab the GPS from the helm
and get the new routes ready to go before the waypoint comes up.)
Most any combination you get will require a slightly different solution. So, unless the exact combination you are contemplating has been done by someone in here, you are more likely to find the answer in a forum dedicated to the software/hardware you will be using.