Q: My iphone 5 goes "no service".

Me too. Haven't had this problem with this phone now since February, but I also changed networks and the network settings reload automatically from Vodafone NZ where-as when I was having issues I was on 2Degrees NZ and network settings had to be restored manually if lost or corrupted. Reset of network settings and updates has cued it for me but this phone only ever did it once whereas previous phone happened up to 4x in one day. Modem  Firmware revision is still at 3.04.25, where first started at(I think check my previous posts) 1.00.16. First phone was at 1.00.00. Really feel for anyone having to put up with this as was driving me nuts. So happy with phone now this is behind me. Good luck with this!

I'm thinking that too Jacks1964 but that's what the Apple Store advised me to do they said back it up from the old back up if that doesn't work order a new sim from EE if that doesn't work go and get another phone.

Update 2: Right I have just done the "Erase all Content & Settings" reset & set it up as a new phone so I have absolutely nothing on this phone, as soon as it switched itself on I got the No Service sign & within the past 10 mins I've had it 4 times, so looks like the problem had nothing to do with me backing up from a previous back-up, I also reset the network settings, I'm going to ring EE to get them to send me a new sim card.

I'm now on the verge of launching this phone out of the window & going back to my 4s because I had no issues with that.

DELETE 8 BALL POOL IF YOU HAVE IT IN YOUR IPHONE 5 ! Ive been having this same "NO SERVICE" problem sonce 3 weeks ! deleting this app fixed it !! try it !

EE have now cancelled my contract after just 6 months with them. They have reverted me back to Orange and I've sent them my iPhone5 back. They admitted that it's a problem that many are suffering and there didn't appear to be a resolution for me.

I have now switched to Vodafone with an iPhone 5 with perfect signal (don't have 4G though!).

Thank you Blassiz! Removing 8ball pool fixed the problem!

UPDATE 3: I don't have 8 Ball Pool on my phone Blazzis in fact I have very few apps but thanks for the advise, picked up my new sim card at 11am yesterday worked for 30 mins then started again, got back on to EE whol esculated it 3 times with no conclusion, I got a call today from the top technical man (which was a miricle in itself that the phone was on that long) he tried to tell me it was the phone because my hubby's phone works all the time on the same network he tried to tll me it couldn't possibly be that because if his works mine would work too....I think he thought he could tell me anything & I would believe him, just waiting for him to call back now so he can compare both phones at the same time.

I have the same issues but they only started a few days ago , previously I had LTE selected on with no problems on 6.1.3 . On returning from NYC ( back to South Africa) I got the no signal problem. Tried all the fixes including network reset to no avail. Reading posts about corrupted Apps I deleted the last one I installed ' Mailbox ' and voila no more problems

I do have the same problem in Ecuador, I run out of signal. First I thought that it was the cell company Movistar, then I moved to the company Claro and still have the same problem. Iam thinking on changing my cell phone.

What is the solution? is it IO 6 or the hardware. I would appreciate an answer?

It is NOT a hardware problem. 6.1 solved the problem for for the swedish carrier "3".

Me and all the iphone 5 owner with the carrier 3 had this problem until the update 6.1 came out in february. Since then it works perfecly. Many, many people got a replacement with no success. Big waste of time and money. I am very surpriced that Apple replaced so many units. They should have knowed it was a software problem.

Well I still haven't had a solution, EE told me that for some reason my phone is trying to connect to an old Orange mast 5 miles from my house & struggling to do so hence I have no service the whole time & my hubby's phone is connecting the mast about 200 yards from my home & that's why he always has signal, EE said there's nothing they can do & refused to call me back so I'm just about to take it further as there is no point in having a phone you can't use

Further to my post , the phone started doing the same thing again . I have switched off LTE and the problem has not reoccurred . Seems like one cannot use LTE on the phone.

I have this problem on my iPhone 4 on the three network I get no service on my phone at least 20+ times a day it's starting to annoy me I updated my phone to latest iOS 6.1.3 as I thought it may have been due to fact I had not updated hoped that would solve the problem sadly not I've restored it switched on and off to try and get signal bk on I even went on to change settings from auto carrier connection to manual which helps it stay on longer but it does still go off reset all settings and still same the fact that so many ppl with diff versions of iPhone seem to be having this same issue makes me think its not the networks but apples iOS that must be bugging as if I'm manually selecting carrier it shows the 3 (3G) as well as voda, 3 (no 3g network setting), EE, etc but seems to only want to connect to the none 3G version of my network and sometimes it lies and tells me I have 3G n signal but when trying to use Internet says I'm not connected to Internet but symbols at top show it is this only happens when connected to wifi with full signal tells me I'm not connected to Internet so I'm thinking that iOS 6 version Modem settings must be where it's bugged also but what ever it is this is apples issue not the networks I've had my phone on contract which is due for renewal at end of June (when rumours of iPhone 5s/6 possible preorder or release date is estimated) so kinda hoping my phone will last til then so I can upgrade but if I have a faulty phone apple best be replacing it or fixing for free as this is their mess my phone was perfect til other week when this started and believe me when I go to apple store in Leeds this week to ask them the unlucky person who has to deal with me wont know what's hit him or her and i wont leave that shop til i get answers or a replacement phone **** hath no fury like a woman scorned as they say

I'm on my 4th iPhone5 as this no service issue will not go away no matter how many restores, deleted apps or any other tricks people suggest. I'm with T mobile / EE but its apple who have replaced the handset everytime. Bloody rubbish, wish I still had my trust i4!!

Further to my post , my phone started doing the same thing again . In South Africa the only fix that works permanently is to switch off LTE and rely on 3G and Edge for Internet use . LTE is not practicable on an iPhone on Vodacom's network , that seems to be the bottom line