diff --git a/app/controllers/attachments_controller.rb b/app/controllers/attachments_controller.rb
index 0c7e35fdc..a3ae9887d 100755
--- a/app/controllers/attachments_controller.rb
+++ b/app/controllers/attachments_controller.rb
@@ -44,8 +44,9 @@ def show
       flash[:error] = "Error loading #{@attachment.name} from #{@attachment.filename}"
       redirect_to([@course, :attachments]) && return
     end
+    # Set to application/octet-stream to force download
     send_file(filename, disposition: "inline",
-                        type: @attachment.mime_type, filename: @attachment.filename) && return
+                        type: "application/octet-stream", filename: @attachment.filename) && return
   end
 
   action_auth_level :edit, :instructor