Hi Vaughan,
Try reformatting the drive first. For updating Windows 10 from an external drive, please refer to this
article.
Regards.
Thanks. I already tried both of those. Update would only recognize the E: drive in the mcroUSB socket as external storage, not the D: drive in the microSD socket, even though both drives were usable for everything else. But Update would also not treat
the D: drive as part of internal storage either. It's a mystery to me why Update can't see the D: drive.
Could it be that Windows is treating the E: drive as external storage but the D: drive as internal storage, and that the latter is confusing Update?
This is a problem because the only way to keep the tablet plugged in is via its one microUSB socket. The OTG power at that socket only goes one direction at a time: it only accepts power for charging the tablet when not being used for an external storage
device. So to do an update I first charge the tablet to 100%, then replace the power cord with a microUSB storage device (currently using a 64GB PNY DUOPOWER), then get to worry whether the battery has enough during the update. Currently the update to 1803
is taking ages: it went from 1% to 2% over the past half hour, I don't see any way to tell the battery's state of charge, and I'm afraid something might go wrong if I unplug the E: drive during the update in order to supply power for a while. (It would be
nice if there were a way to pause update in order to do so.)