I lost my etrex 30 and replaced it with the new etrex 30x. I haven't been able to load NW Topos on the new device, either in native memory or my 32GB microSD card. I'm using Garmin Base Camp on my PC with NW Topos, and I click the Maps menu, then Install maps...
It spends an hour and a half installing NW Topos, then reports that it failed!
Is anyone else out there using the new etrex 30x or 20x? Garmin's docs don't even mention the existence of 3rd-party maps, so they''re no help. It's quite possible I'm doing something wrong - I haven't found a function to format the SD card for Garmin, for instance, but I wonder if Garmin has "improved" this model by forcing it to accept only Garmin products. As much as I like USGS maps, I need the additional trails displayed by NW Topos!
Jan. 12, 2016: It works! I'd been using the eTrex 30x to save tracks for later viewing, without a decent map set in the unit. When I plugged it in with Garmin BaseCamp yesterday, it offered to update the unit's firmware. I did that, then thought to try loading NW Topos once more. It took most of 2 hours, but this time it worked! I now have the details and the little-known trails that make my GPS useful to me.
Here's the other surprise: when I unplugged the USB cable and restarted the unit, it spent several minutes loading the new firmware I'd downloaded. That means that when it successfully loaded my new maps, it was still running the old version 2.10 firmware, not the 2.30 I'd just downloaded.
My best guess is that staying busy on the computer, rather than leaving the room and letting it go to sleep saved my map download.
I could be wrong, but I recommend disabling your PC's power-saving options for the duration of the map download to the GPS, or keep using the computer so it doesn't sleep.
NW Topos is such a good mapset for us Washington outdoors types that if the 30x hadn't worked with it, I'd have traded down for the earlier model.