The Multiple File Upload tool in Blackboard allows you to upload multiple files into your course folder by dragging multiple files or folders into the upload box rather than uploading one file at a time. Unfortunately, this tool requires a Java Applet to function properly. Google Chrome and Microsoft Edge do not support Java Applets. Trying to use the Multiple File Upload tool with either of those two browsers will result in a grey box and you will not be allowed to drag multiple files or folders.
1) In order to use the multiple file upload tool you will need to use another browser, specifically, Mozilla Firefox(Windows or Mac), Internet Explorer 11(Windows) or Safari(Mac).
Note: Be sure that you have the latest version of java installed in your computer.