Friday evening I had the following message pop-up on my phone.

http://i.imgur.com/oijS9JI.png

I immediately tried to sort the problem myself. I tried toggling about with mobile data etc, reset the network settings and performed a hard reboot. Nothing worked. So I called 3 and battled with the advisor. He first took me through all the of the toggle this toggle that stuff, which I followed. He then asked what version of iOS I'm running (7.1.1) and told me it is out of update. We squabble over this a bit back and forth, I ask him to stay on the line whilst I check for any updates, there are none. I tell him again there are no updates and my device is already running the latest version of iOS, so he placed my call on hold and went off to check this before coming back and apologising for the error.

After I tried everything he concludes that there is nothing else to try other than a factory reset of my device and sends me instructions via a text message on how to do this. There was no way on earth I was going to go perform a factory reset on my phone so I left it. Later that evening I noticed that my personal hotspot had returned and I felt pretty smug that I hadn't had to factory reset my device.

However I've tried to enable hotspot again and am given the same message. So this time having my iPad to hand I remove the SIM from my iPhone and place it into my iPad. I am presented with..

http://i.imgur.com/kT1iAwa.png

So that to me pretty much confirms there is no issue my end and that something is wrong with the SIM/network. I know of all the avenues to take next.

I've posted this here to ask whether anyone else has had the same problem? (I'm hoping someone has!) I'm not that active here anymore so wouldn't have read about it if someone has touched on this already, I guess reading through several pages a day of squabble doesn't appeal to me anymore)

What plan are you on, and how much data have you used since your rollover date? as new One Plan pay monthly plans only include 2GB of tethering now.

One Plan before it was changed. It is intermittently allowing tethering.

I should have mentioned that, crossed my mind as I closed the tab.

Get Three to reset the internet profile on your account.

An interesting issue.

If resetting some account setting could resolve the issue it's surprising that was not performed when the problem was discussed with the 3 support staff. A training issue perhaps? Factory reset on a device is not the most welcome suggestion as that involves reloading all of the cloud based data so it's understandable that you would only want to perform that as a last resort.

A meaty support issue for sure and one that I look forward to reading the resolution of.

Is this something the guys on 333 will understand?

So I've called 3 a few times this morning.

Called at 10:15, call lasts 26 minutes. I get taken through various steps and transferred to Apple Care, or 'the Apple' as the advisor describes it. Apple go through some steps and we speak about the problem, on the basis that the problem is present on both the iPhone and iPad we agree that the problem lays with 3. End of call.

Called at 10:44, call lasts 10 minutes. Advisor asks me to go through some steps and personal hotspot returns. End of call. Within no longer than 30 seconds the hotspot feature has vanished again.

Called at 11:04, call lasts 35 minutes. Advisor wants me to go through some steps again and we do expect for the resets since I explain that I have already carried these out. She then transfer my call again to Apple, the Apple advisor says I should go to either a 3 Store or an Apple Store for a replacement handset.

Shortly after I try to call the 3 Store at Broadmead and Cabot Circus, both calls fail to connect. (Numbers not in use??)

Shortly after I find the emails I had with EO a few weeks back to find a number for them a reference. I dial the number given in the email but am met with an automated message saying the number is no longer in use, see three.co.uk for alternative contact methods.

11:54 I call on 333 again, call lasts 9 minutes. I explain the fuss with trying to arrange an appointment for a replacement handset and am told this needs to be arranged via Apple. I am transferred to Apple Care again and the advisor reiterates the problem is with the network and not the handset as I have the same issue with the iPhone and the iPad. He/We have a little giggle at how silly and frustrating it of 3 to be passing the buck on this one.

So that's a total of 80 minutes spent on the phone and.... nowhere near getting a resolution. I have noticed though that the problem only occurs whilst my handset is on 3G, as soon as I switch over to 4G the option is back again and functions. Have this explained this to 3 but it obviously has had no impact.

What a frustrating experience. Big problem when the network and the hardware manufacturer can't seem to pin down what is causing the problem. With Apple being a premium product one expects a premium level of service. Its a shame the CSRs are not reading the notes clearly to avoid repeating unsuccessful resolution attempts. Strange that LTE is unaffected and yet 3G has been. I guess all you can do is escalate the issue and try to remain patient.

I completely understand where Apple is coming from. I personally believe that this is a problem with 3, otherwise it wouldn't be following the SIM card between my iPhone and iPad, that is works on 4G but not 3G adds to that theory.

I am writing out an email now with clear screenshots and explanations of anything and hopefully can have someone call me back to discuss it soon.

My mum got another carrier update over the weekend. I wonder if this did anything to the APN settings?

I am seeing my parents this evening so will have to try and enable tethering to see what happens (they both have an iPhone 5s and are on the One Plan, from last year so still with unlimited tethering).

It does seem like it's a problem that will be fixed in due course, hopefully without people having to call customer services who might be clueless if they've not been given any information (as it's down to an unexpected problem). Three MUST be aware of the problem as it must affect everyone with an iPhone. Of course, not everyone will be tethering, so may not notice.

Back in the day, Apple introduced the whole concept of tethering and it became possible for a network to charge extra for it. This was perhaps the worst thing that Apple ever did, and I don't let off the networks (O2, AT&T etc) for allowing it because they thought that they'd make a nice bit of extra money, shared with Apple. Until this happened, tethering wasn't a 'thing' - you just used data, and whether it was on the phone or via a USB/Bluetooth connection to another device (later Wi-Fi) was entirely up to you.

It seems that this is now what Three perhaps intends to do. Not just having a PersonalHotspot APN, but making it so the account has to manage it separately (something enabled on your account) - which I guess makes it easy for the iPhone/iPad to control usage and keep users within a 2GB allowance (or whatever).

But I also have no idea how Three intends to implement this on other phones, such as Android?

Note: I made a couple of edits during the time the above was quoted below!

Thank-you Jon. I haven't received any carrier updates and am still with 16.1.

I should perhaps add, before anyone jumps to conclusions, that she may well have ignored the update before. I saw it when I updated her phone (iOS update) so accepted it.

I can check what version it is later too, if I remember!

I have had a search of Twitter, searching the error message and have only been able to find one tweet from back in 2012. The conversation doesn't look promising, Three didn't have any solution to tweet back. So it seems I may be riding this one solo..

Why not back up the phone and try the factory re-set on at least one piece of kit ?

Hi mate, what an annoying situation and such a LONG time spent on the phone all for nothing it seems!

Me and the wife have been with Three for 4-5 years and have never seen this issue until now, we are both using iphone 5' s and with the 16.1 carrier update, no issues at all.

If you've done the basics like toggling data/airplane modes on and off, restarting the phone, hard reboot, removing sim/turning off phone, then I think your pretty much forced into doing the restore unfortunately. Either way your going to have to reload all your apps whether you sort this phone OR get a new one. Extremely annoying but sometimes it's gotta be done!

My wife's iphone 5 had this issue where by whenever there was a software update it wouldn't update over the air on the phone, it would always throw up an error message, so for about a year I was updating it for her over iTunes which seems to take 10 times longer than OTA, so there was me updating my iphone OTA in about 5-10mins and hers would take up to 2-3 hours! In the end I restored it, ever since it's been fine. Hopefully that little story might make you feel abit more confident about going ahead with the restore.

I really don't see how a reset will help. If the issue follows the SIM between my two devices, how can the software/device be at fault?

One Plan sim only still allows unlimited tethering?!?

Of course it does.

Oh yeah I forgot that, perhaps it won't help then but if it's to do with Three why hasn't other people experienced this, and why doesn't google bring up more results of others having the same problem? Very strange.

I really don't know what to suggest, if you get to the bottom of it then be sure to let us all know

Get a new replacement SIM card from three shop?

Is it worth BSing and saying that "tethering doesn't work" (like you get the "go away" web page) rather than a specific iPhone issue?

Perhaps if they can reset something that would normally fix that, it would also fix the phone issue.

How does the iPhone tethering block work anyway?

I am not sure anyone knows.

I didn't get to see my parents yesterday, so I couldn't try it out on an iPhone 5s.. but I will hopefully at some point this week.

I'm intrigued, as until now Three just let you use data as normal. If you tether, it either works or Three detects it and gives a warning (or not, as is common).

By having a different APN, Three must think it can manage it more effectively - essential for keeping users to a limit that is separate to 'normal' handset-only data. And an iPhone can be set to allow, or disallow, tethering in software (thus allowing an operator to charge for it).

Could it be a setting on the SIM that didn't happen, thus the phone doesn't allow tethering? Could it just be a setting on the account that didn't happen (the same update that Three users needed before they could access 4G)?

I don't know, and can only guess.. but I'll repeat what I said above; if this is how Three is going to try and manage tethering, how will it do so on other platforms? Or indeed if you just took the SIM out and put it in another phone?

I assume that the carrier provides a standard web-based API that allows the phone to ask if Tethering is enabled for a particular account. If it is, then the option works, otherwise it shows the error message.

I believe tethering is controlled by the carrier file on iOS devices.

That's right. Carriers are supposed to push the profile to the iPhone when the SIM is inserted in a device. It determines such things like whether the Enable 4G switch is active and the whether tethering is allowed etc. I have seen provisioning problems before with other networks and they can usually sort it out.

OP have you ever connected the phone to iTunes on your computer? That can sometimes prompt for 'Carrier Settings' to be loaded on the first sync. Another way is directly from the phone go to Settings > General > About, and it may prompt you download a carrier profile.