Hi guys,

I bought a Samsung Galaxy Y about 5 or 6 weeks ago. The phone worked fine for about 2 weeks, but after this period I started to get messages like "Invalid MMI code" or "not registered on the network" when attempting to make phone calls. Also, text messages don't go through. I can't receive calls or text messages either. In order to determine the problem I tried a SIM card from another network and it started happening again.

So, I went to the store where I bought it and they replaced it with a brand new one (same brand and model)... The problem started happening again. Not knowing what else to do, I replaced the SIM card (same carrier, same number) but it's still happening. I'm really clueless about what to do because everything points to the phone, but it would be a really bad coincidence getting two defective phones, so what I can infer is that the quality of this phone is really poor, or there is a bug in the software.

When I went to the store to have it replaced, they told me that if the problem persisted, I had to upgrade the software. Problem is, Samsung is not releasing upgrades for this phone, so if I want/need to upgrade it, I will have to use one of these 3rd party firmwares out there. I have a question, though: Is it legal in England to root phones and use custom firmwares? I know about the risk of bricking the phone; I'd only like to know about the legal side of it, at the moment.

Oh, and a couple of things that might be relevant: the problem occurs randomly, but occurs most of the time, which renders the phone useless. Also, despite this problem, the internet works without issues on the phone (through wi-fi and through my network's internet services).

Any ideas about what can be wrong?

Thanks for any help!

IANAL, but I have no reason to think that the use of 3rd party firmware is illegal in England. in fact, I have reasons to think that it isn't, but who really knows until it is tested in a court of law?

However

1. It'll obviously void your warranty (or, better said, will give the shop an excuse to claim that your warranty is voided even if they told you that it is what you have to do).
2. At this point, you should still have the 'ok, this model of phone doesn't work, just give me my money back' option - if the purpose of a phone is making and receiving phone calls (and that can be debated, but that's OT as it is enough for it to be either implicit or explicit in the normal understanding of the capabilities of a phone) and it doesn't make and receive phone calls, then its not fit for purpose, within the meaning of the Sale of Goods Act
3. As far as I can see, the symptoms you have are symptoms of the network failing to take calls from you (and, possibly, route calls to you); this may be a phone problem (eg, somewhere in the deep magic of the phone there is a setting wrong) or a network problem (something is marginal in the network that doesn't like this phone, but isn't problem for other phones) or it may be a sim problem (number double registered/de-registered, intermittent connection to the sim), but it isn't really your problem - "if you don't give me a phone that works, I am not prepared to pay" is presumably a workable response
4. One possibility would be to get a sim that the shop will "guarantee' will work (in as much as that word has a meaning here) and then get the network to transfer your old number to it (presumably, once you have confirmed that it actually works)

That's the bit that makes me think that possibly your phone is being seen by the network as illegitimate; the wifi bit doesn't go over your provider and is fine. You might think that the fact that your provider's internet services is ok is counter-evidence, but I'd bet for billing and QoS reasons they treat the two lots of traffic separately, and, if so, I'd bet that blocks on the two lots of traffic are separate, too.

Hi salasi, thanks for your help.

I guess it's possible the network "believes" my cellphone is not legitimate (it's Giffgaff, by the way), but I wrote to them explaining the problem and they didn't tell me anything about my cellphone not being recognised. Also, I've tried two different SIM cards from two different networks but the problem still occurs. By the way, I don't experience the problem when using my Giffgaff SIM card in another phone. So everything seems to point to the Samsung Galaxy Y.

I'm too under the impression that it might be some obscure setting somewhere in the phone, but I have no idea which one. By the way, I saved the settings Giffgaff sent me when I first inserted the card (I think these are Internet settings anyway). Something else: I did a factory reset on the first phone (the one they gave me before I had it replaced by the new one) and the problem persisted after that (can't remember if I did it with the new one too, but something tells me it won't work ).

I think I will follow your suggestion and ask to have my money back (or have the phone replaced with a different brand or model).

Well, I uninstalled Whatsapp last night and the phone's been working fine since. I will have to test it for a few days more before I can be positive it was due to Whatsapp, though... In any case, does anyone know of similar issues with Whatsapp? Or reformulating the question in a different way: is it possible for Whatsapp to interfere with the normal functioning of the phone blocking SMS and calls?