My list of printers is blank when I select "Network Bulk Print" and attempt to use that option.
Add a printer to the Ediscovery/Summation Pro application server, via its IP address (i.e. do not use Windows printer name).
"Network Bulk Print" prints to printers added at the application server.
Note: "Local Bulk Print" prints to printers added at a workstation. If the list of printers is empty at the workstation, add a printer to the workstation, via its IP address.