Originally Posted by baktas87
No. You repair it?
went through the same problem after updating from 4.3
I repaired the baseband and IMEI by flashing 4.3 modem on 4.4.2 stock rom.
You can try it too. Get the modem of your model from here and Flash it TWICE through odin.
Flash with Odin in CP
(Not in AP) . Two times by manually rebooting
into download mode after first flash.
Make sure you get the modem for you specific model.