Plug-in distribution system, image processing apparatus, plug-in distribution control method

A plug-in distribution control method comprising:

• controlling, when distributing, from a distribution server to an image processing apparatus via a network, a plug-in to which distribution settings data defining a distribution destination and the number of distribution times concerning the plug-in and usage settings data defining the number of usage times and transfer permissions concerning the plug-in are appended, a distribution destination and the number of distribution times concerning the plug-in by using the distribution settings data;
• and
• controlling the usage of the plug-in by using the usage settings data if the plug-in is used in the image processing apparatus which has received the plug-in from the distribution server, and controlling the transfer of the plug-in by using the usage settings data if the plug-in is transferred to another image processing apparatus.