Why am I unable to send or receive MMS messages after the Oreo 8 upgrade

[Android Central Question]

Since running the update to Oreo 8 on my unlocked Galaxy S8, I cannot send or receive MMS messages. I have tried various messaging apps, including Samsung's native Message app, but with all, the problem is the same, unless I completely shutdown Wifi and run on mobile data only.

 

[kurt424]

I'm having the same problem with my Unlocked Note 8 on Sprint. However, it still doesn't send on data either. The Samsung native app also won't let me attach a video to the chat message. It says that the file is too large.

 

[Gilly14572833]

You have to go to settings and erase the network settings it also erases mobile data settings and after that you will be able to send and recieve mms