Why can't I successfully program the Stratix device on the Stratix PCI Development Board (Standard or Pro edition)?

Description

If it appears that the Stratix device immediately restarts configuration and reverts to the factory image, the reason may be because there is contention on the board with the unused pins in your design. To avoid this problem, you must set all unused pins in your design "as inputs tri-stated." This is a Quartus II setting found in the Assignments -> Settings -> Device -> Device & Pin Options -> Unused pins.