The Short Version: Depending on the network environment, network authentication may block iMessage text messages. In addition to blocking messages to and from iPad and iPod touch devices, it will also result in blocking iPhone text messages. The simplest work-around is to disable iMessage in Settings -> Messages or just disable WiFi.
iMessage is a useful feature. It’s available in iPads, iPhones, and iPod touch devices running iOS5. Simply put, it provides the ability to send text messages over wifi and/or a cellular network without using SMS. It’s more useful for iPad and iPod touch owners with wifi-only devices. For example, someone using an iPod touch can send a text message to a person with an iPhone.
At first glance, it’s a great concept. It’s integrated into the default Message app. Unfortunately, some users may find it completely useless. Specifically, it’s a problem for individuals that connect to wifi networks that require authentication and also require continuous activity to remain authenticated.
I do. I’ll forgo the details of where or how but in order to access the wifi network from my iPhone I must login to the network using a Web browser on the device. I’m required to re-authenticate after a set period of inactivity, so I can’t just login once per day and be done with it.
This affects my ability to receive text messages via iMessage. That’s not to say I’ve never received a message without authenticating, but there were probably other reasons it seemed to work (perhaps my device had just switched over to the wifi network at the time or maybe I authenticated earlier and then forgot that I had done so).
This effectively blocks the usefulness of iMessage for some. To cause further problems, the iPhone seems to already know who does and does not have an iMessage compatible device. If I text another iPhone user it will default to sending the text message via iMessage.
In the Message app the iMessage texts are colored blue. Standard SMS texts are colored green.
To work around this problem I’ve switched the iMessage feature off (Settings -> Messages). This means that I can’t receive text messages from iPod touch or iPad (wifi-only) devices, which is unfortunate since my wife recently received a new iPod touch for Christmas. However, it seems to be a better compromise than disabling wifi.
Note that this isn’t a problem with network authentication methods. In fact, they’re working properly if they are blocking iMessage to unauthenticated users. I’m not sure Apple thought this through. Granted, most users may never deal with this problem on a regular basis, but Messages should at least be updated to automatically, and immediately, send a text via SMS from the iPhone if it can’t be sent via iMessage over wifi. We’ve come to expect text messaging to work almost instantly and somewhat reliably.
Updated 04/11/2012: Instead of disabling iMessage I’ve started turning off WiFi and use only the 3G connection. Obviously this is only a possible solution for iOS devices that have mobile data plans so it won’t work for an iPod touch.
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I think this is exactly right. The question is why the message registers as delivered when it was blocked–doesn’t the network have a way of knowing when an iphone receives a message? It can register when a message is read, but not when it is delivered? Further, why doesn’t the iphone default to cell data when wifi is not authenticated? Can’t the iphone tell it isn’t authenticated?
Apple did not think through. However I think this is a fairly common situation for students on college campuses using the campus wifi.
Steve – That’s an excellent point. It’s a problem I have also noticed and one that I should have included in the original post. Before I realized this was a problem I thought a couple of people were ignoring my messages because they were marked as delivered. An accurate confirmation would be very informative. Several of the messages that were marked as delivered were never received by the recipient. At least with SMS messages you know for certain whether or not they were delivered and you can easily resend them.
Right, turn off wifi and it works fine.
I do notice that while the message says it was delivered, it never says it was read.
With SMS you get an exclamation point that will when touched allow a resend.
I have just started getting this problem here in Australia. Even the phone (4s) is having trouble deciding which is an iPhone. It’s stating that a house phone number can receive imessage.
It started this weekend, been trying to text our daughter, she was not getting the imessages, so turned it off then sent her a message low and behold she received it
Experienced this problem (or at least realized I was having it) for the 1st time today, Weirder, IMessages replies did not go to my phone, but did go to my iPad. Did some experimenting using my wife’s iPhone as the other of a pair, found she could both send and receive, while I could only send. Her phone had just come in the door and reconnected to our WiFi network, mine had been at home for more than a day. What worked for me (in Canada, on the Rogers network).was to turn WiFi off and back on in Settings on my phone, and reconnect to the WiFi network; now I can send iMessages between the phones in either direction. It would be nice to know how long it takes for a phone to have to re-authenticate. Barring that, a work-around that might do is to turn WiFi off an on before initiating a message session,
My phone is playing up in exactly the same way. Can send, but not receive, iPhone wifi messages, but my iPad is working fine. So annoying! Am now in the process of turning wifi off & on again on phone. Had no issues before I upgraded to iOS 6.
I have an iPhone 4s and my wife has my old iPhone 4. She does not use mobile internet while roaming, so we have switched off cellular data on her phone, When at home, she can use internet through a Wifi connection. The problem we discovered is that when I send her a message it defaults to iMessage and is marked as “delivered”. However, she does not receive the text message until she returns home or connects to a Wifi network. To get around this, I have started turning off iMessage on my phone before sending to her, so the message gets sent as a standard SMS and is delivered immediately (as long as she has a phone signal).
In my opinion it would be a valuable addition to iOS if there was a setting to disable iMessage selectively for each contact, thereby forcing the messaging service to use SMS for particular contacts, rather than having to switch it off in settings.