Originally Posted by NYCHitman1
Have you attempted a factory reset yet?
Yes, I did last night and it helped me pinpoint the problem.
First I booted into safe mode and the problem still persisted. So I tried a factory reset. With no apps, it was working perfectly. So I started reinstalling my apps one group at a time via titanium backup. After each group I would check MMS. Got all my main apps installed and working perfectly. Then I installed some others that weren't a big deal. That's when MMS stopped working again.
At this point I was a little confused because I thought safe mode was supposed to boot up with all 3rd party apps disabled. And since MMS didn't work in safe mode and I pinpointed the fact that it was indeed a 3rd party app, I was confused.
So I go back and do another factory reset. Only install apps from the Play Store. It is all working great so I do a nandroid backup to store my progress so to speak.
About an hour ago, I installed adblock again and MMS stops working. So I'm like "dang it, that's the problem. Got to uninstall it." After I uninstall it, MMS still won't work. So maybe there are some left over files that it couldn't get rid of when uninstalled? I'm not entirely sure.
But I restored my previous nandroid backup where I knew MMS was working. Didn't have to make any major adjustments after that, just a few setting changes here and there.
Ultimately, it looks like adblock was the culprit. Everything worked until I installed it. Then even after uninstalling it and rebooting, it still didn't work, so I had to restore from my backup.
Hopefully this helps anyone else who has had the same problem.