How do I get my iMessage to turn back on?

Turn iMessage Off, Reboot, And Then Back On. Head to Settings -> Messages and tap the button next to iMessage to turn iMessage off on your iPhone or iPad. Next, hold the power button down until you see 'Slide to Power Off' and slide your finger across the bar to turn off your iPhone or iPad.Mar 13, 2015 read more

Go to Settings > Messages and Turn OFF and then back ON your iMessage option. Now open back Message and try to send a message to your friend 's iPhone, but make sure to use the button at the Top-Left corner to find your friend and start the conversation, don't just open your recent chat with him/her. read more

Most likely, however, the iMessage functionality was somehow turned off completely. When the iMessage service is turned off, all messages will be sent as SMS instead. You can turn the iMessage feature back on by heading to Settings > Messages and flipping the switch for iMessage from OFF to ON. read more