How to fix invalid IMEI problem after flashing Android Device

It's always better to take a backup of your IMEI numbers with some kind of restore tools before flashing your device. Because after flashing or installing custom ROM your IMEI numbers will be wiped out. Find this post to see how to take IMEI backup and restore it.

Unfortunately if you did not take a backup there is no need for worry. Still you can make a backup file using your PC and restore it with mobile uncle tools. But this app needs root permission. See the process here. But if you do not want to root your device you can use the following method of writing IMEI number manually to solve invalid IMEI problem. But if you reset your phone you have to write the IMEI numbers again.

First go to your dial pad and type *#*#3646633#*#*

This will take you to Engineer Mode. Go to connectivity tab. Tap on CDS information.



Now click on Radio Information > Phone 1.







































At the top of this page you will find AT+


After AT+ write EGMR=1,7"IMEI number"

It should be like this: AT+EGMR=1,7,"123456789101112"

Now just tap on SEND AT COMMAND and after that restart your phone.

If your phone has two sim card slot repeat above process for
Phone 2 (AT+EGMR=1,10,"123456789101123") and restart your phone again.

Now check your IMEI number typing *#06# on your dial pad. Your no network issue is now solved.

Find this video for video tutorial on how to restore IMEI number manually.