This is a Galaxy S3 I9300 (international version) that I've had on T-Mobile (happily and with no problems) for years.
I've been running CyanogenMod for ages on this phone, and after they closed up and LineageOS took up development I switched to that. Everything's been working great until recently. I'm not sure of when it started but I can't download group texts. As noted in the subject line, calls and regular one-to-one texts work fine.
Details, in case they're important:
LineageOS 14.1 (nougat 7.1.1) built on 2017-03-29 (updated to see if that helped, it didn't)
Using OpenGApps also built on 2017-03-29 (also updated to see if it helped)
Using Google Messages for SMS app.
I checked my APN and it's set to T-Mobile US LTE
There's also a T-Mobile MMS entry in the list, but I don't know if it's settings are right... it's enabled (and that's grayed out) but I don't know if the other settings are right.
Username, password, authentication type are all "Not Set", along with a bunch of others.
Any ideas of where to look?
Never mind... 10 minutes later I find the setup guide for sms on non- t-mobile phones. Duh. I guess those settings got lost in a partition wipe or something, because the MMSC and other stuff wasn't set.
Now that it is set up correctly again, everything's working a treat!
Have a great day, everybody!
Glad you found the answer!
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