Attempting to burn DVD with windows movie

Hello,
I am attempting to burn a video I downloaded onto a DVD. I made the movie and have it in Window Movie maker. When I press the "Burn" button. I get an error message that says "please insert blank disk into drive E". I have tried several different disks. both DVD+R and RW. My coputer says that drive E is functioning properly. Can anyone offer any advice. My comp is a Dell Inspron 530s and is about a year old. Thaks for the info!