In addition to workflows for a case folder, a case folderās attachments can also have an associated workflow. These workflows are always adhoc workflows.

Enable Adhoc Attachment Workflow: When enabled, a case folderās attachments can have their own workflows; documents will then be able to be assigned as tasks to users, and the assignees will have to complete the assigned task on the documents
Attachment Workflow button text: Determine the text on the Attachment workflow button. This option is hidden until Adhoc Attachment Workflow is enabled