Why is there a red exclamation point on the message icon on my ipad

Yes, that is the situation; I've had two different models iPhone (5c and SE) with some kind

of hand-off. ~ Just short of Continuity because these iOS and my Mac's OS/X vary enough

to not specifically utilize the easier 'continuity' setup. - And iCloud plays a part, plus wi-fi.

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

A device 'inter-relationship' is critical for that aspect to work & to see expected results as suggested.

Yet some of the 'circled red ! marks' were due to sending from iPhone to other iPhone users.

{Because I was using the iPad and rarely post to ASC from there, I wasn't able to add links or edit my

replies while online.. (also have no shared library of support bookmarks) ..within 'time-out' limitations.}

Thank you for pointing out an important detail.

Tap on the exclamation point. You should then see the explanation.

My guess is you're trying to send a message to a person without an Apple device to receive it, as iPads only transmit iMessages to Apple devices.

When using my iPad Mini1.1 (16GB) wi-fi only w/ iOS9.3.x those red circled exclamation points

suggest the message was not delivered. And about 30% of mine are sent to non-Apple users.

But that's not why they don't get sent. Could be the servers or your ISP, or perhaps a local glitch.

Happens with my Apple contacts, too. With iPhone and also Mac with the messages application.

There sometimes appears to be a connectivity or handoff issue between different vintages of OS.

Sometimes a message goes through or not, and at times the error or red ! mark only shows in

the iPad, the same message went through in the iPhone. And sometimes instead of iMessage it

goes to Apple device users as Text message.

Maybe some homeless gremlins have taken residence in iPad for the season, or in network. When

odd issues occur, I check to see if my devices and Mac can see each other. And find at times they

are "off-line" or not visible. I've found the Find My iPhone helpful, to reestablish their awareness.

Anyway, it's 3:44AM and I need a few hours sleep...

Good luck & happy trails! 🙂

🌞🍀🏕🍄❄🌎

FYI, when considering K Shaffer's response, there is one very important point to note:

K Shaffer states: "And about 30% of mine are sent to non-Apple users."

Be very careful when considering that. An iPad, whether it has cellular data capability or not, cannot send a message to a non-Apple device. Sending messages to non-Apple users requires an iPhone, and that iPhone must be associated with the iPad using Apple's Handoff protocol.