You may also have to look at replacing some hardware. PC boards are designed to have constant power fed through them, when a system is switched off over a prolonged time period the circuits, resistors, transistors etc can degrade. As a result the hardware will not function as desired.
Humidity, resulting from temperature changes during storage can aid this degradation process along nicely.
Carefully pull out all the cards and inspect them for any visible watermarks, rust, dust etc.
Contact your vendor to assist you, I would start with the core equipment, power supply, then work my way throug the rest. This should keep you busy for a while
