@abidali thanks for the info about the factory reset.
abidali That keep the 7z archive is intended for internal storage only. When you download on internal storage and then select it manually to update without extracting it.
I tried that after my first try from the USB didn't work.
Copied the 7z to the root of internal storage. Chose it in OTA update, Local install.
3 mins copying (why?), then checksum error, even though the file checksum is correct (I tested).
@DUDU-Meng said before that "The offline upgrade feature can only select 7Z files for system versions that have been pushed by the server; other test versions will fail validation".
With that being the case, you'd think it would do a very quick check that the version number is acceptable, before doing a full copy and checksum. Ugh.
They really should add some useful error messages in that OTA update app, or correct the instructions in the first post here.
Or both.
