HMS-EN2PB-R HMS-EN2PB-R “16#012a invalid output application path”

I added HMS-EN2PB-R to 1756-L83ES but keep getting the following error code “16#012a invalid output application path”. I can browse the HMS-EN2PB-R in RSLinx. From the local rack I can get online with, I browse to the HMS-EN2PB-R through a Remote I/O private LAN to another EN2TR, then through the back plane to get to another EN2TR and out to the HMS-EN2PB-R from there. In configuration Manager, I cannot even scan the network. Do I have to be online on the same private network as the EN2PB-R? See attached IO tree config.
IO Tree


Someone else had the same problem:

They found it was actually an IO size problem in the PLC.

Actually, this might be the problem. In order for the Configuration Manager to work, you do need to be connected to the same TCP/IP network.