Someone in a different discussion solved the problem for me.
The solution was to setup the iPhone 4 as new and not do a restore and then FaceTime worked.
I have the same problem - after iOS 7 update my phone cannot successfully establish a FaceTime call.
I have three iphone 4 and an iPod 4th gen, all devices except one can FaceTime call each other using our home network, but one iphone fails connecting with any other device.
I am not going to restore my device, there needs to be another solution as the settings are identical to the others. Still searching for an answer.
Same for me. Have left feedback bug report for Apple.
iPhone 4 iOS 7.0.2 calls iPhone 4 iOS 7.0.2 and says connecting but never connects.
So disappointing. My father is 91 and using FaceTime between different countries was amazing. Most disappointed with Apple's lack of community communication around this issue. Is there a public bug report board that Users can view? If not, Apple, why not!