UPS: The local network management interface-to-UPS communication not established.

[Pete89]

I have several of these Smart-UPS SRT 5000 all running UPS Network Management Card 2. I replaced the batteries and then did a firmware upgrade:

Since then communication to the UPS has been lost. I have tried Resetting All, Reboot Management Interface. I shutdown the UPS itself which still says I need to replace the batteries despite the fact that they have been replaced and a self test was done. I was able to deaden the UPS by shutting off commercial power. I left it completely shut down for a few minutes. My research has led to believe that the firmware that was loaded was not the correct one, but I have not been able to find firmware for the model number of this NCM v2 which is AP9537SUM. I find it hard to understand how the wizard would allow me to use incorrect firmware and call the installation successful if this is the case.

POST EDIT:

It turns out I was allowed to load the incorrect firmware. I searched for a while for the right firmware. Using the model number of the NCM gave me zero results in the search tool, but eventually after reading lots of documentation I found it. 

The NCM and the UPS are now in communication with each other. The file you need is this: APC_SUMX_716_EN.zip 

I hope this post helps someone someday.