If you click Browse to upload a document and receive an error message in red showing the following Error in red "Duplicate file is not allowed" it means that the document they are trying to upload is a document that was already uploaded.
Example of the error on the Documents tab - Here they just need to move on to the Filings tab to select the document.
Example of the error on the Filings tab - Here they just need to move the document from Not Selected over to the Selected side by clicking the arrow.
