About two weeks back, Apple released the first major update to iOS 7. The latest iOS 7.1 update come with new features and enhancements. However along with fixing many issues, iOS 7.1 has caused issues while using Personal Hotspot Feature. The iPhone users are unable to save APN settings for Personal Hotspot feature.
Discussing the issue in detail, most of the users getting the issue are iPhone 4 users. Also, their carriers are unofficial ones (not recognized by Apple). The issue emerged at Apple Support Communities while the content now reaching to 17 pages. Here is what some of the users say:
I talked with Apple, they said that the problem should be at my carrier. I phoned my carrier(Telenor Hungary) and I told them my story, they rejected me eith the reason that the problem is with the phone. I took my friends SIM card(T-Mobile) and I put it in my iPhone. Guess what, tethering was available and working.. Then I called my carrier back and told them my experience then they told me that the problem could be that they(Telenor) are not official sellers of Apple and in iOS 7.1 it became more strict, that devices wont connect to these networks. My quedtikn to you is that whether your carriers are official resellers or not. because for example my carrier apn settings are not pre-set in iDevices. :/
(psychoo118)
Same here. Hotspot not working since I upgraded to 7.1. Such an annoying issue. I phoned my carrier this morning and they didn’t want to get involved since “it’s a device issue since settings can’t be saved”. No carrier updates either when I installed 7.1. So right now, no hotspot and no one wants to get involved.
(caaf.au)
So what the actual issue is? Well, when you enter values in APN field, it apparently does. But later, when you try to save the values you are unable to do it. Thus, making it impossible to undergo a connection without any parameters.
Apple has not announced the removal of Personal Hotspot feature yet. However it seems that Apple has gone bit strict about unofficial carriers. So from now on, only authorized carriers like T-Mobile will be able to enjoy the Personal Hotspot feature. We will keep you aware as we get some more updates or solution for this issue!
Source: iDownloadBlog