1794-AENTR fault code 16#0106

We have a DLR network with a few flex IO racks. One of the 1794-AENTRs is faulted with code 16#0106, which does not make much sense being a DLR network that only has one controller. The 1794-AENTR also shows Internal State: Program Mode. The connection is unicast. I have worked with many 1794-AENTRs and don't recall ever seeing something like this. The controller is for a furnace, so there are not too many things we can do since we run 24/7. Any ideas are appreciated.

Welcome to the forum!

My quick search of the knowledgebase did show up one technote on a 1794-AENT, where this error was caused by a duplicate IP address. If it were me, the first thing I'd do would be to note the IP address of the fsaulted device, remove it from the ring, connect my laptop into the ring, and see if I can still ping that address.

code 16#0106 is "Connection Request Error: Module owned and configured by another controller". Could it be that the PLC was changed and the
1794-AENTR has not been power cycled and it is remembering the previous owner? Is it possible to power cycle this one 1794-AENT?

Thank you both for the replies!! I will see if we can get a chance to power down the AENTR to ping the IP address. And the power cycle is what I wanted to try since we just had a power glitch last week and maybe it did not come up correctly. I have tried to uncheck the unicast connection since everything is inputs on the bus, but that did not change its status.