Signal Tap II - Invalid JTAG Configuration (using USB Blaster) (Cyclone IV)

The message "Instance not found" is telling you that this design does not contain this instance of SignalTap II.

Once you've created a SignalTap II instance, you need to add it to your project, and then re-synthesize the design.

The SignalTap II GUI normally asked you if you want to add this instance to your project. If you said no, then you can still add it, you just have to go to the Assignments->Settings menu, and under Category select SignalTap II Logic Analyzer, set the path to the instance, and check the check-button to use it.

Cheers,

Dave