I had the same problem. I was unable to send pics, but could receive them. Completely stock, no flashing/rooting ever, using stock Text Messaging app. I also noticed when I clicked on the Boost ID icon that it said the Boost Network was not detected. That was the case from the beginning (had some issues when activating the phone), but since I could call/text, etc and didn't want ID packs I put it off.
I called Boost and went through the rigamarole, which led to typing in a number being led to Reset. I asked, "will this erase all of my settings and everything on my phone?" "No, we're just resetting the network" or something like that.
Of course it did reset my phone, went back to day 1 looks with tutorials on the screen and everything. Oh well, SD should have most of it. Pics are working and Boost ID connects. Hang up, and then realize my Voicemail is dialing the wrong number as my phone number is programmed wrong in the About Phone section.
Call back, fix that, number is showing correctly. Assume all is well, hang up. Find that I can't text or call at all now. Call back and go through more resets and updates. Now all better be well, because each call led to a new problem.
At least my original problem is fixed. Now I just have to recover what I can. I backed up a couple weeks ago and meant to backup right before I called, but it slipped my mind. I can see some stuff in My Files, so hopefully if I re-download an app it will be recovered (such as ColorNote notes).
Just realized, Boost ID is again saying Boost Network Not Detected. UGHHGHGHGHHHHH!!! I don't care about ID packs, but if there's any indication of something not working I want to get it fixed before I set my phone up again, lest they have me reset and lose it all again at a later date. For now I'm resting for the night, already spent over an hour and they did mention at various steps that some things would take time to reset. Wish me luck, I'll update with changes. I can still call/text and send/receive pics.
Sorry, I meant to just report how I got my problem fixed with some warnings, but it turned into a rambling.
Update: The Boost ID not detecting network is because I was on WiFi. Turn WiFi off and be on 3G and it works. So it looks like everything is working on my phone now.