My GEE2 is currently running on version OPM1.190831.007, and I can't find a way to get a more recent version running. I've tried the flashing tool and manual flashing, but both methods came with their own issues. I'll give them below:
Flashing tool: I get either a 'device already in use' connection error or the device is offline. This besides the more common message that the flashing tool has some problems on windows sometimes, and that I should try refreshing the webpage.
Manual flashing: once I have given the adb reboot-bootloader command, the fastboot devices command won't recognize the device (listed as ???????? instead of the device name/number) or it will be offline. As a result, the commands that should be given afterwards according to the Readme file don't work.
I have the adb debugger from the Android Studio SDK platform-tools folder, so I updated the driver software of the GEE2 with the use of that folder initially. Afterwards I tried installing other adb software as well but that didn't help either.
I have also tried a couple of the simpler solutions, as unplugging and plugging, refreshing the site, using another computer, using another internet browser, deinstallation of the driver software, a factory reset of the GEE2, installing less recent firmware instead of the latest. None of these things changed the outcome.
Any suggestions would be highly appreciated!
I had similar issues with Windows, the driver, and fastboot not working using the flash tool. I was told by support to use a USB 2.0 port. I used a Mac with USB 2.0 to flash it and it was successful.