TLDR: Through lots of trial and error, I managed to get outbound MMS working - here’s my story.
I recently purchased a Murena Fairphone 4 and had a really good experience out of the box except for one thing - sending MMS photo messages was hopelessly broken. Literally, everything else worked great:
Calls in & out
SMS in & out
After quite a bit of back and forth with my carrier (Mint Mobile) confirming APN settings and them resetting the SIM card on their network, they eventually gave up, blamed it all on Murena and /e/OS, and said they wouldn’t support me any further. I started troubleshooting things myself, found this forum with lots of other MMS complaints but no solutions that worked for me, contacted Murena support (who I am sad to say have yet to even reply to my initial inquiry), and even hit up the nice people over in the Telegram support group. After many iterations of DNS setting changes, manual MMS proxy settings that my carrier disapproved of, turning various things on & off, rebooting, etc. I had gotten exactly nowhere. I eventually started trying changing various things out in my APN settings, and that’s where I eventually solved the problem by simply adding
xcap to the ‘APN type’ setting. For anyone else on Mint Mobile, here’s the exact settings that made everything work for me as of the time of this post.
Proxy: Not set
Port: Not set
Username: Not set
Password: Not set
Server: Not set
MMS proxy: Not set
MMS port: 8080
Authentication type: Not set
APN type: default,supl,mms,ia,xcap
APN protocol: IPv4/IPv6
APN roaming protocol: IPv4/IPv6
MVNO type: GID
MVNO value: 756D
I don’t know for certain, but I suspect that this might also work on T-Mobile, as Mint Mobile is an MVNO that exclusively operates on the T-Mobile network here in the US. Best of luck to everyone else out there having MMS issues!