A Duplicate Document ID exception is generated when new document is generated with the same file path name as an existing document. Typically this happens at output time, when two or more input pages have the same Document ID barcode.
To avoid this exception
If your process expects duplicate Document ID's, and wants to see them combined into one output file.
Set the On duplicate Document ID exception field the Output Panel to Append
If your process expects duplicates, but wants them kept separate, then:
Set On duplicate Document ID filed in Output Panel to Create unique file name. Unique file name is created by inserting string _NNNN_ before extension of output file, where NNNN is a four-digit number starting with 0001 for the first duplicate output file.
If the business process does not tolerate duplicate Document ID at all
Make the Session ID part of the output folder or the file name. In this case only duplicate Document ID in the same session will generate an exception.
Make sure that no duplicate ID documents are present