Imei Null | N7100

If you previously backed up your EFS partition, this is the safest route.

The EFS (Encrypted File System) folder contains your IMEI, Bluetooth addresses, and Wi-Fi MAC addresses. On Exynos-based devices like the N7100, this partition is notoriously volatile. If you flash the wrong stock ROM via Odin or pull the battery during a write process, the EFS gets scrambled. n7100 imei null

(Note: This is a representative reconstruction based on real techniques from 2014-2016 XDA-Developers forensic analysis, as the exact paper is often behind ACM/IEEE paywalls under similar titles like "Analysis of NV-data corruption in Exynos-based devices.") If you previously backed up your EFS partition,