No email service when using the 3G network

No email service when using the 3G network - I purchased my Blackberry Torch in December and it?s worked perfectly until 3/3, at which time I can no longer send or receive email using the 3G network. Using wifi, everything continues to work fine. When I?m out of wifi range or have turned wifi off, email is dead, but I can make calls and browse the internet just fine. So far, I?ve 1) Removed the battery and card, waited a minute, and put them back in 2) Deleted all of my email accounts (4) and re-added them 3) Sent service books. All four showed up as fine once I turned the wifi back on 4) Upgraded all of my apps, and deleted any I wasn?t using 5) Registered the host routing table (I think I did, when I clicked, nothing happened) Now what? A mobile device that only works at home is not helpful. Thanks, JJ