The Encore WT8 tablet that I was testing was just installed when suddenly the battery was not detected any more, even though the device actually was running on batteries.
Interestingly, I couldn’t find any one with the same problem, but I tried the usual stuff, resetting bios to default settings, exhausting the battery etc.
Finally, it was solved, but I’m not certain which step was the actual fix. Or maybe it was a combination?
Anyway – I upgraded to bios 1.60, but had to hack the installer as it has a battery check. “Insert system battery”. Unzipping the bios-installer with 7zip, twice, you get access to a platform.ini-file, where you can change a line to BatteryCheck=0, and then run the flasher. I needed the BitLocker recovery key from Microsoft to boot again, restored bios settings, did a proper shutdown, and finally powered it off by pressing the power button and volume up.
The last part was found on the Microsoft Surface support pages as Solution 4 to battery problems.
My device now has bios v1.60 and embedded controller 0.84, so it’s probably a very early unit.
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