The Accumulate Printing Mode is a feature only available in PDF2XL Enterprise, as it requires access to the Cogniview Printer, which is an Enterprise-only option.
The purpose of the Accumulate Printing Mode is to open more than one document at a time in PDF2XL. This is handy if you have several documents you want to convert into a single Excel file, or if the documents have different layouts (which makes the Enterprise Batch Conversion tool unusable).
Using Accumulate Printing Mode
Open your first PDF in Adobe Acrobat (or whichever PDF viewer you use).
Use your Print option and choose the "Cogniview Printer" as your default printer; this will open your PDF in PDF2XL.
Click on the "Accumulate Printing" button from either the Start tab or the Home tab.
Open the next PDF in your PDF viewer and print to the Cogniview Printer again; you will see the second document open in PDF2XL
Continue step 4 with all remaining PDF files, then proceed with mapping your layout and converting your documents.