It seems that the No OS Found Error in TWRP recovery becomes one of the common issues among Android device users while flashing the firmware zip file via TWRP. If you’re getting into the custom development segment or trying to flash external stock firmware, you’ll require a custom recovery. Well, TWRP (TeamWin Recovery Project) recovery is one of them, and it should work without any help from other programs such as Magisk.
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It’s always recommended to take Nandroid backup of the device data and wipe out other device partitions before flashing a new firmware file via TWRP. Now, if we talk about the custom firmware flashing, wiping out partitions includes Data, Dalvik, System, Boot, Vendor, etc. So, if you’re also facing the same no OS found error that means there is a boot partition issue on the device and the recovery program can’t detect the installed system whatsoever.
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