Visual Editor not allowing image uploads

When I try to upload an image with my visual editor, after I browse my computer and select the image file, I get this message, for example: “acousticfoamvscarton.jpg” has failed to upload due to an error
Unable to create directory /var/www/vhosts/acousticsblog.com/httpdocs/wp-content/uploads/2012/04. Is its parent directory writable by the server?
This is for all images, not just one. Any ideas?