[blue68f100]

He is at the version that support the snap, post 16. But there were several upgrades afterwards that addressed the APC snap issue. I think the UPS feature worked at the earlier release, with v 4.2 adding the usb support. I know mine worked with v4.1.

At this point see if there is a newer firmware for the APC. I have gone through 3 version on my Smart-UPS. And it still has a bug with the snmp server settings. Since this feature was added at a later date your APC Firmware may not support the GuardianOS.

Did you restart/reboot the APC Network card?

Did you remove the IP from the client list and add it back in?

Is the UPS in the same subnet as the 4500? The APC uses a broadcast (udp) to anounce it's presence, I do not recall which port it's using. If on a different subnet it will not receive the broadcast.

The auth phase in the APC is the same as the key in the 4500.

Then for one last shot before we take them to the field and shoot them. Remove every thing you have added, clearing all fields and saving, then reboot the units. Since most apc support more than one device, just reboot the network card in it. Then follow the instructions again. I feel one or two things are happening. APC FW does not support the GuardianOS. And or it's brains are scrambled from all of the changes. If you used ascii for the key, use only hex chr this time, 16 chr long.

Are you using the email function in the APC card function and/or snmp traps? Look at the log may give you some insite, as well as the log on the 4500.

What is the model of APC-SmartUPS and which Network card is in it.

A mute point at this time:
I noticed you have a large (early) delay on the shutdown for low battery. Any particular reason. Having a large number may not drop the power to the 4500, if your sheeding load. Without dropping power to the 4500 it will not auto boot on startup. One of those catch22 things I ran into during my testing.

None of the other users I helped with this issue didn't have this much difficulty. Most worked the first time. Which kind of makes me lean to a APC fw problem.

Try to see if it will work with a usb cable? But I do not recall if it gives feed back on connection status.