Not registered on network (samsung s4 mini)

Hi xenium,

Have you tried this steps?
- Set Network mode as WCDMA only and restart your phone. After restarting, follow below steps.
- Go to Settings.
- Go to Wireless and networks.
- Tap Mobile Networks (If mobile networks not found then tap More settings and then find and tap Mobile networks).
- Select your Networks operators.
Let me know this helps or not.

Thanks & Regards,
Krunal T. Tailor

Hi krunal, thanks for your suggestion. What and where is network mode WCDMA? I can't see this option. I have it on network mode "3G only"
Cheers

For me this is where i find my network mode. (I have Galaxy advance with Gingerbread Android OS - old version)
settings -> Wireless and network -> Mobile network -> network mode

This may be very device to device, WCDMA option come for those who purchased mobile with company plan.
tell me if this helps.

"when i flew to Bogota the phone refused to register with any network, even though it was able to detect a list of providers" -> it seems to me that it is t-moble uk which causes the problem as it is some authentication issue when you can detect the network but cannot connect to it.

when did you buy your S4 mini?

Hi Jackie,

Yes i thought that too, so i persisted over an hour on the phone with T-mobile trying all their combos and then going up to level 2 support, still no luck.

I bought the phone around July 2013

Cheers

I should add that the T-mobile sim card works fine in another handset.

The problem has mysteriously resolved itself, after a couple of weeks of refusing to register it now does so. No change to the set-up.

Any ideas how this could have happened?

Though basically case is closed.

My wild guess is the latency between the mobile network your s4 mini and the nearest signal tower is lower than the threshold and the authentication has failed from the high latency.

Thanks Jackie. What is this latency in laymans terms? If still relevant....

Meanwhile....

The problem has taken a new twist.

Initially the problem disappeared without doing anything. Then I had the phone unlocked so I could use it with another SIM card. The phone continued to work ok with the original SIM card and also with a SIM card from another operator. Then one day when I switched back the original SIM card I got exactly the same problem again "Not registered on network". I mention the phone unlocking just in case, but I don't think it is related as the problem existed on and off both before and after the unlocking.

The original SIM card continues to work fine in another phone, so again there is no issue with my phone account, the sim card, or the operators roaming deals.

I'm still keen to resolve this though, so any further comments are welcome. If necessary I will repost with a link back, as the question has been assigned as abandonned, sorry for delay in coming back.

Update: I'm now in Mexico and the phone works again with my original sim card. My guess is that Colombian service providers have some systems to deter phone theft, eg sometimes you need to register the phone's IMEI in order to use a service providers sim card.

Maybe when i switched sim cards in Leticia, the network registered an anomaly and thus blocked my samsung from working. It's a wild guess, and i don't know the ins and outs, this is all i can think of given that 1. There appears to be nothing wrong with the phone 2. There's nothing wrong with my service providers roaming agreement in Colombia and 3. The phone worked with a local sim and local service provider.

Ok nuff of that.

Thanks all for your input.

The problem will remain a mystery...