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1 Why can't I software update?
I bought a Samsung Galaxy S4 about a year ago and got it unlocked for t-mobile. Everything works great but I am unable to do software update. When i try to upgrade it tells me service unavailable. My baseband version and model number is still under Verizon, I tried to change it but don't know how and nothing I tried worked. I have android 4.4.2 and i know that there is higher and better software. Also I really do not want to root my phone to get an update. Any one know how I can get the latest software.
Hi,
Just a few thoughts and I don't know if all are correct or will work. Do you know anybody with a 'locked'Verizon phone, or who uses Verizon that you can 'borrow' the SIM card from, just to do the update? I'm assuming that the 'update server' info in your phone is part of the 'customized' OS firmware placed in by Verizon. If it does work you may lose all of your downloaded apps and user data as it may be overwritten with the OS upgrade. I don't know if this is correct or not, but maybe it is better to assume it is. Also doing a backup will save your data but possibly a restore from the backup may run into problems because of the OS upgrade, so it may be better if the OS upgrade succeeds to manually reinstall all the info and apps. Also not sure if your phone will be 'locked' to Verizon again. You will probably also have to set it up again for your t-mobile connection
jayeff さんによる