If the IMEI appears but you have no network (null/null), you likely have a .
Boot the device into a custom recovery mode (like TWRP) or connect it to a specialized flashing tool. Select the "Restore" option. Locate your original NVRAM/EFS backup file. Swipe or click to restore, then reboot the device. Method 2: Using Professional Service Software
Find your original 15-digit IMEI number. Check the original box, purchase receipt, or the sticker underneath the physical battery.
To perform these repairs, the following conditions usually apply: Root Access
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If you created a backup of your device’s EFS or NVRAM partition before the corruption occurred, restoring this backup is the safest and most reliable method.
This method is typically used when the IMEI has reverted to "Null" but the hardware baseband is still intact. Prerequisites A computer running Windows 10 or 11. A high-quality USB data cable. Samsung USB Drivers installed on the PC. installed.
Once your IMEI is restored, protect it. A single mistake can wipe it again.
The phone will reboot, and the software will verify the new IMEI. 3. Patch Certificate Procedure (Essential)
Locate the exact factory stock firmware file for your C7100 on your PC.
Essential for putting the device into specialized modes (like Download Mode or EDL) if conventional methods fail. Step-by-Step Guide: C7100 IMEI Repair Procedure
The Samsung C7100 is powered by a Qualcomm Snapdragon chipset. Unlike Exynos-based Samsung devices, Qualcomm devices store critical network configuration data, including calibration parameters and the IMEI, within specific partitions known as the and NV (Non-Volatile) RAM . Common Causes of IMEI Corruption
A dominant software suite for Samsung repairs. It allows direct EFS wiping, NV data editing, and direct IMEI rebuilding via ADB interface.