Sometimes after flashing feature phones, the phone ends up with imei loss and shows null or invalid imei when you dial *#06#. Thus device has no network service.
This is a short tutorial which will show you how to restore the imei on feature phones using SN Write Tool.
Learn how to flash feature phones from here
Note
Changing of imei is illegal. Use original imei found at back of the phone.
romkingz is not responsible for any damage caused using this tutorial
Do this at your own risk
Download sn write tool from hereDownload and install feature phone drivers from hereExtract and launch SN Writer.exeComPort select USB VCOMTarget Type select Feature PhoneClick System Config
Under Write Options, tick IMEIUnder IMEI Option, tick Dual IMEI if you want to restore for both SIMsClick MD1_DB and select the database file (Found inside stock ROM of the device)Click SAVE to exit System Config
Click START buttonEnter the IMEI numbers and click OKWhen you see message showing wait for USB insert,Connect phone to PCWhen a message PASS in green is seen, process is complete.Insert battery and reboot phone.
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