This paper describes detection and notification of component failures in distributed component-based robot applications using the blackboard architecture. The blackboard architecture monitors each component of robot applications in order to detect component failures at runtime and it identifies the causes of failures. Using the dependency relationships between components, the blackboard architecture performs impact analysis between components so that it determines the scope of failure notification in the components of a distributed robot application. The notification messages delivered to components can trigger actions against the failures if robot application developers have implemented the actions along with application functions. The prototype of blackboard architecture has been implemented for the Microsoft Robotics Developer Studio (MSRDS) environment, and it has been applied to the Unmanned Ground Vehicle (UGV) application implemented on the simulator as a case study.