Description
Design software support for FLEX, APEX, ACEX, and HardCopy Stratix device families is not provided in versions of the Quartus II software beginning with version 9.1. Use the Quartus II software version 9.0 or earlier to support those devices.
Resolution
Refer to the section Design Software Support for Mature Device Families in the Quartus II Software Device Support Release Notes (PDF) for the Quartus II software version 9.1 for details.