Help cannot connect to network

[mpf1981]

Hi There Guys,

I have a problem. My brother has given me his old phone (samsung s3) which doesnt work. Before i start i know he rooted it and maybe done other stuff to it.
I have put my sim card (o2) into it (i know the sim card definately works in other devices) and i keep getting the error selected network unavailable. when i try to connect to a network i get the error 'unable to connect. try later' under the about device- status page i can see the following errors:

Network: Unknown
Service state: Out of service
Roaming: not roaming
Mobile network state: Disconnected
Bluetooth address: Unavailable
Device status: Custom

the imei number is correct.

Is there anything i can do to get this working again?

Many thanks for any help

 

[girolez]

Hi

Start by checking that the APN settings are correct for your sim provider:

menu
system settings
more settings
mobile networks
access point names

Edit them to be the same as in your working phone with that sim (I assume you have one)

 

[mpf1981]

Hi girolez,

Have done, still the same result

 

[Hadron]

Rooting shouldn't do anything here, though knowing what other mods he's made (especially if he's messed with radio firmware) might be useful.

Firstly there's the very basic test: go into the phone settings, find the network selection menu and search for available networks. If it can't see any then the problem is with the phone radio, one way or another. If it can, then select O2 and try to register manually.

If it won't work, and especially if it can't see any networks, it might be worth checking that there's nothing funny about the network settings. I assume that in the phone menu it's set to 2G/3G mode? If you want to dig deeper, type *#*#4636#*#* into the phone dialer (no need to press the call button). On most phones that brings up the hidden "Testing" menu. Select "phone info" and then look for "Set preferred network type" and see what is selected. You want something like "GSM/WCDMA auto" or "WCDMA preferred" ("WCDMA" is what's commonly called "3G"). Do not change anything else in that menu, just hit the home button when you are done. It's a long shot, but there are options there that you don't find in the regular phone menu, so if someone played with those and set it wrong it might stop you seeing any network.