First of all, excuse my terrible English. Some time ago I bought another one eTrex 20 on eBay, it has a beta firmware version 1.16. As usual I tried to update it with the latest firmware 4.80. To my surprise none of the ways to do it works for me.

1. Usual way by Garmin Express and WebUpdater doesn't works, the firmware remain the same.
2. Updating by GUPDATE.GCD doesn't works too, device just doesn't see this file at all.
3. I tried to use more old versions down to 2.20, but it doesn't helps too.
4. I tried to update the divece by Updater.exe and RGN file in boot mode, but device stalled on step "Loader loading..." and some time after it Updater.exe show me error:

App: Updater
At: 1/4/2019 9:59:58 AM (UTC)
OS: WIN32 Windows Platform, Major Version: 6, Minor Version: 2
Processor: Pentium Pro or Pentium II, RAM: 2097151 KB
IOU_UTILITIES.CPP-203-2.8

I tried Windows 7 and 10, result is the same.

I need an advice, which way I can update my eTrex 20 to the lates firmware version?