If your IMEI is showing as "null/null" or "000000," you generally have two paths to recovery. 1. Restore from a Backup (Recommended)
💡 before any modification. You can use root-access file managers like Root Explorer to manually copy the /efs folder to a safe location. j710f efs file
Some J710F users report even with a good SIM. That's often a semi-corrupt EFS – the phone reads the IMEI (so *#06# works) but the radio certificate is damaged. In this case, the modem refuses to register on any network. Your only fix is a certificate rewrite using a box tool. If your IMEI is showing as "null/null" or
You can't simply copy someone else's EFS to your phone; that would mean two phones sharing the same identity, which is often illegal or simply won't work. The story of the J710F EFS file is often a lesson in digital mortality If you have a backup, you are a hero. You can use root-access file managers like Root
Enter (Press Volume Down + Home + Power simultaneously). Connect the phone to your PC and launch Odin.
The "interesting" part is the community hunt. When a user forgets to back up their EFS before tinkering, they enter the EFS Recovery Quest . They scour forums like XDA Developers