Online Help | Web App
You can replace an attachment (file or link) or edit its description on the Attachments tab of an open record window. In addition, you can modify file attachments when you are performing a workflow action, from the action window.
To modify an attachment:
On the Attachments tab of the object record window or in the Attachments section of the workflow action form, сlick Properties. The Edit link window opens.
To modify the link location, specify a new location in the Link field. To edit the attachment description, type it in the Description field.