You are asking a 'split' question here !

A 'keygen' is an application that simply generates registration 'codes' in order to 'activate' protected programs.
They produce semi-random 'answers' which correspond to the 'rules' that a program expects to be 'observed' when an activation code (sort of like a password) is entered...

'Phone challenge codes' are simple... When people buy, yes... BUY... software over the net, they are provided with different methods to use in order to 'activate' the software... 'Activation' is NOT the same as 'registration'.
The Phone challenge code is a number you give some semi-sentient object on the telephone and then, with some luck, said demi-zombie replies to you with an 'activation code' which will make your hot little paid for program actually work.

Simple, hmmm ?Because the particular program you are attempting to 'steal', as far as copyright protection is concerned, has been set up to require 8 boxes and 1 small box to be filled with info which meets the general requirements of the definitions of the activation code decided upon by the legal owners of the software that you are trying to steal !

I bet I can almost certainly guess what the program is... Like, it might start with an 'N', hmmm ? It all depends on how you do it and whether or not you do everything in the precise order... BUT, whenever you attempt to possibly do any updates or 'definition' changes, you run the risk of being nailed for piracy... Geddit ?

And, ain't no such thing as a free lunch... Just crumbs to nibble on until the big guy comes in to sweep up, right ?

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