I've seen this error ages ago, and it was definitely related to a corrupted database or corrupted gpx or geocache file giving the not enough memory error on boot up as other people have posted.
The factory reset SHOULD reset the database, but if not, connect to a PC, then you go to DEVICE\Garmin\GPX directory on the eTrex 10. If you want to back up the GPX files you can copy them on to your computer first, but then delete them all.
Then after disconnecting the eTrex 10 from the computer, restart it, this forces the eTrex 10 to rebuild its internal database, and hopefully get rid of the memory error.
Failing that, the last time the eTrex 10 firmware was updated was in April 2019 to version 3.60.
https://www8.garmin.com/support/downloa ... sp?id=5555 If you aren't on 3.60 upgrading the firmware would be good too.
If you don't want to use Garmin Express to update the firmware, let me know. I can grab the GCD file and give you manual instructions to update it.
The eTrex 10 has a really low memory is a pain (8Mb on board), compared with the eTrex 20 or 30 which had 1.7Gb. But that shouldn't be an issue for recording 2 tracks and 8 waypoints like you have. It does seem like a corrupted file issue.