IOS – Why did iMessage stop working after upgrading to iOS 8.2

iosmessagessoftware-update

After updating to iOS 8.2 I got a message saying "Your SIM sent a text message." Then I tried to send someone an iMessage and it sent an SMS instead even though that person is able to send and receive iMessages.

Best Answer

I guess the message is for security purposes(citation?) and for some reason it turned my iMessage off. Turning it back on fixed all my issues.