I can not send text messages to Android users comes back message failed

In order to send messages to an Android user from your iPad, it will need to be paired with your iPhone. On your iPhone, go to Settings>Messages>Text Message Forwarding, select your iPad and follow the directions.

See this article for more information:

Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support

What solved it for me was to turn iMessage off then delete the old message thread that was started with iMessage on. The new message thread started with iMessage off resulted in the messages successfully sending.

i have had no issues with texting Android users in iOS 11.0.3 through iMessage over cellular using my cellular provider.

What are you using?

What if you have it setup as described in the answer, but it fails to send from your Mac?

There is no such thing as “text messages forwarding” in the Message settings on my iPhone 7...

Please disregard previous reply. Both devices needed to be digned in with the base Apple ID...