Recently I faced a dashboard privilege issue which I spend countless hours to resolve the issue.
Create a new group and provide privilege to a dashboard. Pretty straight forward right !!. After creating the application roles and providing folder privileges I was hit by this error message and the error details didn’t provide much information.
After researching and playing around with a lot of the privileges realized that the application role permission has to be set in the catalog manager.
So access the catalog manager and traverse to the path provided in the error message. In _dashboard layout you would see Application Roles assigned to this path. Add your application role and you should be good.