An action cannot be completed because a component (component name here) is busy. Choose "Switch To" to activate the component and correct the problem.
Above message may appear when trying to access a voting activity, such as the Slide Editor.
The PowerPoint is busy message can appear if PowerPoint has got stuck waiting for something else to happen (e.g. taking a long time to save the presentation) or if it has crashed and needs to restart.
This will often be solved with a restart of the system (rather than just closing PowerPoint) as in this scenario closing PowerPoint will make it appear to shut properly but it can still be running hidden in the background.