I was afraid of that, but then I didn't really look into it too much. Resulting code compiled after the expiration date will function, but may require more memory space.'

After 60 days, the optimizations related to procedural abstraction and to the extended instruction set of the newer PIC18XXXX devices will be disabled. 'The Student Edition has all the features of the full compiler and libraries including support for all devices. In any event, you can see it and its restrictions here: It has deliberate limitations, but anyone serious enough to produce production code would most likely upgrade to the normal version of MLPAB C18 by purchasing it anyway.

I could be wrong, but I would imagine Microchip's intention would be to allow people to get their 'feet wet' with this product. I'm not sure if they tout it as being 'free' or intend for people to use it freely, so hopefully someone from Microchip will respond in this thread about this new Student Version of MPLAB C18. You might want to investigate that angle. Microchip recently released a Student Version of the MPLAB C18 C compiler.

Microsoft free c compiler download