Simply put, a bad ESN* means the phone or device has been blacklisted or locked for some reason and can not be activated.
It might seem like a great deal, but buying a cell phone with a bad ESN is a bad idea. Once a phone is blacklisted, it is problematic
to get it activated again. So if you've bought a smartphone with a bad ESN or bad IMEI number chances are you have a very expensive
brick/iPod/extra drive on your hands.
What makes an ESN bad?
An ESN/MEID/IMEI number can go bad for any one of three reasons:
The phone is still active on the owner's wireless carrier account.
There is money owed on the wireless carrier account to which the ESN/MEID/IMEI is connected.
The phone was reported lost or stolen in the past.
Regardless of the reason, only the owner of the wireless account to which the phone was connected can clear the ESN/MEID/IMEI number.
Our video has more information about bad ESNs. Already stuck with a phone that has a bad ESN? Check out our infographic to discover a few ways you can put it to good use.