Make sure to use a supported browser when working in D2L.
Using an unsupported browser can cause problems working in D2L - such as when submitting Dropbox assignments and quizzes. 
Active students, faculty and staff have free access to more that 1,400 training videos on a broad range of subjects, including business skills, photography, design, music and video, home computing, animation, and web design and development. New Courses are added every week. 

Visit for more  information