Mobile data on but not working I have a Galaxy SIII (Android 4.3) phone on the Vodafone network (UK). I was using WiFi when available and mobile data occasionally. It all worked fine. When on mobile data, I would see an icon on the top bar showing a little letter H with two arrows underneath.

But now the mobile data has sort-of stopped working. I say sort of because it appears that I can still turn mobile data on, and I still get the little H with two arrows, but none of my apps that use data appear to actually be able to communicate with the internet. I don't actually get any "no connection" messages, instead, I just get rotating wheels and other indicators that they're trying to get something that's not arriving.

If I switch back to wifi then everything starts working again.

Any ideas?

EDIT: I have not installed any custom ROM. The phone is not rooted.

EDIT: I just called vodafone, who suggested a variety of things that made no difference. Now they've said it may be a fault in my SIM card and are sending me a new one.

EDIT: New sim card arrived. No difference. More calls to vodafone, multiple suggestions... nothing has worked.

EDIT: Tried sim in Galaxy SII... all symptoms identical. Saw little H icon (sometimes flipping to "H+" or "3G"), but no mobile data getting through.

SOLVED! it suddenly started working again. I suspect it was a fault at vodafone's end and my last call to tech support induced someone there to correct the fault.
TLDR: use a SIM with a different number (no matter if Vodafone or a different service).

We see a symptom (no net), but we have to find out the cause first, to solve the problem. So let's think step by step, what the problem could be.


Faulty phone?
No, your other phone (the SII) doesn't work either (using the same SIM).*
Faulty SIM?
No, you have already tried a new SIM.
Faulty cellular tower?
No, you have already tried an other tower (by changing location).
Faulty Vodafone?
Likely, because I'm sure they have net, and you're sure that they have to give you net (data limit hadn't been reached), plus we've found out in the previous questions that it isn't about the net is stuck between you and them. The only problem here is that you have already asked them, so they should have investigated the issue. But I'm sure they will take a next - more in-depth - look, since all the other possibilites are crossed out now.


I advise you to call Vodafone again, tell them that your phone is ok, your SIM is ok, the local tower is ok, your data subscription is ok, and then there is nothing left to do: they have to accept the fact that there is something wrong with their service. Until that, use a SIM with a different number, I'm sure it'll work in your current phone.

* To be 100% that your phone is ok, try a different SIM with a different number. I think the new number can still be Vodafone, because only your current account is affected (your current number), not the whole infrastructure. However, if you don't want to experiment (and your phone is unlocked), you can immediately get a SIM from an other company, as Firelord suggested in a comment below. (So that you are safe, even if the whole Vodafone system is damaged.)