Iphone 4 failing to send and receive texts/calls

You guys using iOS 5.0.1 (9A406) build? Go to Settings > General > About > Version. Check this out: http://iphone-and-i.blogspot.com/2011/12/fixing-iphone-4s-signal-problem.html

I for one am using that build! I might not be able to do it for a few days but I hope that fixes the issue. I will post here if it does. Thanks!

Yep. The build worked perfect for me. The signal problems never came back. Not once. 🙂

For those of you not using Cellular data, turning it on and then back off will fix the issue.

Settings > General > Network > Cellular Data (toggle between on/off)

Thanks so much djace_ent.

Tried toggling on and off Cellular Data, and it instantly worked.

I recieved a number of texts that were sent over the day instantly.

I have been trying to figure out how to solve this problem without restoring my phone for two months now. I had almost resigned to restoring my phone again for the third time.

I'm having the exact same issue with my iPhone 4S and it is so annoying that there's been no fix! I never had probs before only since I got my 4s and new contract in January. I've restored, rebooted, and I find only way to send the message is to airplane mode my device then un-airplane it!

Come on apple - get it sorted please!

By way im on iOS 5.1

On a side note - anyone noticed since 5.1 that when playing music it cuts songs off at random point?

I have an iphone 4 am using iOS 5.1 and cant send texts to a perticular number unless i turn 3g network access off which drives me nuts as it is the main number i text and everything that uses data is sooooo slow without 3g on. i called my carrier they said they are already aware of the issue and are looking into it. have you tried turning your 3g network access off?