I can receive regular text messages fine. But when someone sends me a picture message I never get it, or if someone sends me a text message w/ a picture never get it as well.

Any ideas why ?

My carrier is AT&T, phone is BB 8700c.

I had this problem too actually and then finally called TMobile. They said it should be working fine, yet it wasn't. I think I then tried re-sending my service books and that seemed to work. So try doing that...

Sorry but don't know what you mean by re-sending service books. Never heard of it.

Sorry if sounding dumb.

Here you go: How do I resend my service books? - BlackBerryFAQ

While this works for T-Mobile, I'm not sure if AT&T works the same way. Try sending yourself a MMS from your own number. I've used this method to get MMS working on a number of phones including Blackberries. Good luck.