We need to know if you:
-have win or mac
-tried loading service books (again)
-tried a battery pull
sounds to me like you might need to reload service books..or reload os
Personally...I would tell anyone...save your money & focus on using a 8350i instead of the 7100. You really don't have as many options with the 7100 as you do with the 8350i. Both, true enough, are older bbs, but the 7100i doesn't allow you to upload ringtones or change the wallpaper like you would like.
Speaking from experience...I has a 7100i that I definately would not have bought if I knew I could have used 8350i on boost.
Hope this helps. BTW, how much did you pay for the 7100i?