I have downloaded all of the necessary packages and programs in order to run the simulation but I continue to get an error of: terminate called after throwing an instance of 'boost::exceptiondetail::cloneimpl boost::exception_detail::error_info_injector<boost::lock_error >' what(): boost::lock_error

The two Camera plugin window pops up and then gazebo appears but without an image just a black screen. Then it closes out giving me the error.
I have ROS Hydro and Gazebo 2.2.

How can I fix this problem?