Secure offline activation process for licensed software application programs

A computer readable medium for activating a software application for execution on a designated computer, the computer readable medium having stored thereon computer executable instructions for performing the following steps:

• (a) receiving an installation identifier representative of the software application and the designated computer;
• (b) computing a blinding factor;
• (c) identifying a digital signature corresponding to the installation identifier;
• and,
• (d) computing an activation code such that the digital signature is a function of the activation code and the blinding factor.

A method of activating a software application offline for execution on a designated computer, comprising the following steps:

• (a) computing an installation identifier representative of the software application and the designated computer;
• (b) receiving an activation code generated in accordance with the installation identifier and a blinding factor value;
• (c) computing a reference value as a function of the installation identifier;
• (e) computing a decryption key as a function of the activation code and a trial blinding factor value;
• (f) using the decryption key to access an encrypted value representative of the installation identifier;
• and
• (f) comparing the encrypted value to the reference value.