Sometimes, attachments may be orphaned, which means that they exist in the specified files directory (to configure this directory, see the section on attachment settings), but aren't assigned to any post(s). This can happen when posts are deleted or edited, or even when users attach a file, but don't submit their post.
To manage orphaned attachments, click onon the left-hand menu once you're in the settings section of the ACP. You should see a list of all orphaned attachments in the table, along with all the important information regarding each orphaned attachment.
You can assign an orphaned attachment to a specific post. To do so, you must first find the post's post ID. Enter this value into the Post ID column for the particular orphaned attachment. Enable Attach file to post, then click Submit.
To delete an orphaned attachment, check the orphaned attachment's Delete checkbox, then click Submit. Note that this cannot be undone.
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