It is possible to change the protocol from Named Pipes to TCP/IP. To do this you need to have the NetworkProtocolSettings.xml file in the %ProgramData%\ABBYY Recognition Server 4 folder that can be generated during the command line installation or executing the ConfigureOCRServer.exe/CREATE_TCP_IP_NETWORK_SETTINGS command on the default Recognition Server installation. The generated xml file may look like this:

- <NetworkProtocolSettings Protocol="TcpIp">
<StationPort>3985</StationPort>
<ServerPort1>3986</ServerPort1>
<ServerPort2>3987</ServerPort2>
<FeedGeneratorEp>3988</FeedGeneratorEp>
<FileStorageEp>3989</FileStorageEp>
</NetworkProtocolSettings>

So, these port should be opened: 3985-3989. The xml file should be placed on both machines: Server and ScanStation. Sure, if you have any other distributed Recognition Server components, it is necessary to place the same NetworkProtocolSettings.xml to that machines too.