User the Trash tab to restore a file or folder that has been removed from Resources.
Select Resources.
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Select the Resources tool from the Tool Menu of your site.
Select Trash.
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Click the Trash tab that is available near the top of the page.
Select the items to be restored, and then click Restore.
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Item is restored.
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A notification bar will confirm restoration of the selected item, and the item will no longer appear in the list.