A standard "Factory Reset" from settings does NOT fix eMMC corruption. You need the UPD procedure.
| Issue | Consequence | Workaround | |-------|-------------|-------------| | | Recovery reset fails (error mounting /data) | EDL mode → fastboot erase userdata | | eMMC hardware failure | Hard reset impossible | Replace eMMC chip (BGA rework) | | Nokia secure boot | Unauthorized flash rejected | Use signed firehose (leaked or official) | | OEM unlock needed | Can't flash custom recovery | fastboot oem unlock (voids warranty) | qm215 emmc nokia hard reset upd
This is the most common method if the phone is locked or won't boot past the logo. Nokia 1.4 - Full phone specifications - GSMArena.com A standard "Factory Reset" from settings does NOT