Forum Discussion
Altera_Forum
Honored Contributor
13 years agoDo you uninstall and reinstall the USB drivers when you change the version of Quartus? Maybe you could try Quartus 6 with the drivers from Quartus 12.
OR as an alternative you can install both Quartus 6 and Quartus 12, and use the programmer from Quartus 12 with the files generated from Quartus 6.