"iMessage needs to be enabled to send this message?

Same thing happened to me. deleting the stuck conversation works. thanks

This worked for me too. Disable iMessage, delete the draft text and the entire thread with that person, start a new text and then it sends just fine. thanks!

Resetting the Network Settings worked for me. Thanks.

Just updated to ios 8.3 and got bubble saying imessage had to be turned on. Toggling it on then off seems to have worked

Agreed! Toggling iMessage does the trick for me, but why can't SMS just work? Stop trying to force iMessage on everyone.

I went to Settings, WIFI, then "Renew Lease". After 3 days of battling with this problem, that's what restored my texting ability.

this helped to get one message out. But, when I turned data back on, it defaulted back to iMessage and now, again, cant send message. Same error is back. 30 minutes into this mess, argh.

Thank you, thank you, thank you! I had this problem with iOS 9 and this solution works still.

Delete the message threads with the contacts that you are not able to send an SMS message to, then create a new message and it should work.

Thanks! I've tried half a dozen things and this is what finally fixed it for me. Really wanted to avoid deleting the conversation thread 😀

Thank you! This is what finally fixed my issue.

I also had luck double tapping, closing the messages app, and trying again. I like to keep my previous messages, so deleting was not an option for me. Glad you figured it out a different way.

disable imessage and just enter the number again instead of using the previous link to that person's messages. That will create a new regular sms text link to that number and green will work

thanks leesehome. resetting network settings worked for me too

What works fine for me is, delete the message and then disable the iMessage and then send a message. The previous messages are lost though.