Create a course Go to Question bank Create a question category Create an essay question type Do the generic question setting (Question name, Question text, ...) Under Response options, for Allow attachments select a number, and for Maximum file size select a size (10KB, 50KB, ...) Press Save and continue editing button and then preview the question. On preview page under the response box you will see the filepicker's message about Maximum file size: e.g. 10MB , maximum number of files: e.g. 2 . For instance if you have selected 2 for Allow attachment and 10MB for Maximum file size; the file picker message would be: Maximum file size: 10MB, maximum number of files: 2 When trying to upload a file exceeding the maximum chosen file size, you will obviously get a popup alert.