Always has "Could Not Activate iPhone" error

As stated above, it's getting this error every time you try activating it, either via local or iTunes activation. Various software resets etc have all been tried. CDMA based unit. Some techs suggested the SIM slot could be damaged. I'm looking for advice what the actual issue is called in the repair world, and if anybody knows a good tech to help with it locally in South Bay Area / San Jose, CA, or via mail order since it's somewhat more involved than a typical phone repair would be.