READ MSG from PLC5E to ML1200 through ENI = FAIL

I have followed KB 19726
My controller is a PLC5E rev J.
The 1761-ENI is FW revision 3.22 .
Connection is Ethernet
SCADA system can read registers in the ML1200 just fine
Logix500 can program the PLC just fine.

Yet I have a PLC5 that will not read from the ML1200 using the following

PLC-5 Typed Read to SLC
Multihop is port 2 to IP address x.x.x.48
ContrologixBackplane to Address 0 (this was part of KB 19726)

The Error is either
Error #18 Connection is broken (if backplane IS NOT specified in multihop)
or
Error #15 Connection not completed because connection was broken
(if backplane IS specified in multihop).

What am I missing here?

My first instinct is to suspect that the Net-ENI is out of TCP connections. It's notorious for only having six; two incoming, two outgoing, and two in either direction.

If your SCADA and RSLogix are both making connections, maybe there's an RSLinx station or something else taking up both of the others, leaving the MSG instruction without a resource.

A Wireshark trace would tell us for sure if it's a TCP problem or some other layer of the system.

There's a Knowledgebase article about using Telnet to read the TCP connection status of a Net-ENI, if you want to check it out that way.

DLG's NET620 will bridge EtherNet/IP to DF1 (Full Duplex) and will support up to ten connections.
http://www.data-linc.com/custom.htm

Yes this thread is old but I did solve this problem and wanted to add the solution.

The ENI MAY SAY it will do 6 connections but it will not reliably. I have 2 of them in 2 different machines and a spare and they all do that same thing. 4 connections max and all is fine. I was able to repeat this over and over again that 6 connections will make it become unreliable.

Wound up using a CLX plc to concentrate the data from the ENI connected ML1200 and having that as its only connection fixed all its problems.