12.2.6 When Starting a Debug Session, I get an Error Stating that Debug Tool is not Set

The reason for this message is that no selected tool is capable of debugging your project. When selecting no tool, it is empty. Clicking on the drop-down menu will show all the available tools. Go to the Tool project pane and change to a supported tool (Project Properties > Tool > Select debugger/programmer).

Check that the correct interface is chosen and the frequency is according to the specification if the tool you have selected supports debug. If the issue persists, try to lower the frequency to a frequency where programming is stable, and then slowly increase the frequency as long as it keeps stable.