Can activation lock checker be relied on?

[iMore Question]

I have an iPhone 4 s dual band given to me by a friend. I have restored it to factory settings and have tried to use it on a new network but keep getting 'activation required' message despite Activation Lock Checker telling me activation lock is off and can be used by a new user. Any useful observation would be appreciated

 

[kch50428]

Can activation lock checker be relied on?

Apple's can... 3rd party? Caveat Emptor.

 

[SwitchBeach]

Was this phone from a CDMA provider (Verizon, Sprint, etc)? This sounds like the carrier activation and not the iCloud Activation Lock.