The majorErrorOccurred event occurs when the player cannot fully initialize. One reason might be that the multimedia dynamic link library could not be found and loaded. Another reason might be that the player could not be found. You can connect an action to this event to inform the user that the player cannot initialize.
majorErrorOccurred is different from the errorOccurred event in the lastError object and does not generate error text. They are distinct so you can easily distinguish between a fatal error and a non-fatal error without having to write any code.
For example, connect to this event if you want to close your application or display a message to the user.