Power cycling it, I could talk to it for perhaps a few minutes, then it would disappear. Then, while it was still powered on, I unplugged it from that switch and plugged it back into my normal Wifi router switch and immediately I couldn’t ping it from a PC connected to that network.

I would just continually ping the IP address of the module from the command prompt.

I tried the following test before: I had a network switch with nothing else connected to it except the IP module and a laptop connected via ethernet. When it first started happening, I suspected it was something to do with my Wifi router and/or its DHCP server - as I wasn’t using a static IP address on the IP module but had reserved an IP for it. I haven’t yet set HA up to use VLANs but I have seen a tutorial on the forum here which looks helpful. I was thinking of putting it on the same VLAN as my security cameras anyway just for added security, but now that you mention it, having it on its own VLAN sounds like an even better idea - and would definitely help to narrow down the issue.

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