Checking the number of machines
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I wish to seek suggestions on th following:

While creating a product key if one wish to use the no. of machines the key is made for , just like in the case of Microsoft Volume Licensing , how can one do that so that easily verfiable inside the dll which is made to verfiy the key entered in the installer and say if a key is made for say 100 machines how does one validate it offline that the product key does not work on 101th computer.

Thanks,
