An IMEI is a 15-digit unique identifier hardcoded into a mobile device’s modem firmware. It is used by cellular networks to authenticate devices and block stolen phones. Corruption of this number can occur due to:

To use the Unisoc IMEI Repair Tool, you'll need:

For now, the tools listed above remain viable for phones manufactured before 2024.

: Errors during low-level system updates or physical damage to the storage module can lead to an "Invalid IMEI" error.