Error (12006): Node instance "cycloneIII_3c25_niosII_application_selector_sopc_instance" instantiates undefined entity "cycloneIII_3c25_niosII_application_selector_sopc" - Error (12006): Node instance "cycloneIII_3c25_niosII_application_selector_sopc_instance" instantiates undefined entity "cycloneIII_3c25_niosII_application_selector_sopc" Description You will encounter the following error if you compile the "cycloneiii_3c25_niosii_application_selector" example design in the Nios ® II Embedded Evaluation Kit, Cyclone ® III Edition, version 12.1.0. This error occurs because the "cycloneIII_3c25_niosII_application_selector_sopc.qip" file is missing. Resolution You can manually add files to avoid this error: 1. Go to Assignments --> Settings --> Files, and select "Add All" 2. Remove ddr_o_bb.v and ddr_o.v from the file list. Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['FPGA Dev Tools Quartus II Software'] novalue 12.1 ['Cyclone® III FPGAs'] ['novalue'] ['novalue'] ['novalue']