@TP-Link 

What was the solution to this, all well and good sending to the inbox but I havethe same issue and now I have no idea if thier fix would fix my issue. Please keep problem solving in the public domain as to help others when they have the same issue.

@seedanielrun I have the same problem, but my router has no option for a Guest Network.  Any idea what else might work?

@ColinP does your router have the option to separate your networks? What router do you have? Are you using a VPN? On your phone does it switch between 2.4 and 5 ghz bands? Just trying to think of what I went through before using a guest network. How many devices on your network? Do you have an access point? 

 you can separate your network to have different passwords for the 2.4 and 5 ghz network that might work but sounds like you may have already done that. 
if you have a VPN it might automatically turn on when you connect to a new network ie your camera's wifi. If yes, then turn that off. If no then......

 if you have multiple networks at your house that your phone connected to, forget the 5 ghz one on your phone. I had 3 and it would automatically connect to whichever one it found first, so if your phone only knows the 2.4ghz then when you do the setup it will go back to the 2.4. 
let me know if

@seedanielrun I have a Plusnet Hub One. It doesn't have a Guest Network feature. I already had to disable the 5GHz network so my Kindle could connect.

I do have a TP-Link range extender that uses the same name and password, this works for most devices I try to connect.

I have 2 mobile phones and a smart TV that are almost always connected and 3 laptops that connect when we want to use them.

I have no VPN.

I did try to connect the C310 by ethernet cable and it appeared on the router's list of connected devices but the phone app could not detect it.

Apart from the Kindle, I've never had any difficulty connecting other devices to the WiFi.

I'm puzzled and can't think of anything else to do except return the C310.

Thanks for your help.

Colin

@seedanielrun I have the same issue, using plusnet. The C310 fails to recieve an IP address.

Has there been a solution to this?

@Steve1234 not really. About the only thing that happened is I made another network dedicated to my smart home devices on the 2.4ghz network. It just worked when I did that. I have no idea why and nothing in the trouble shooting worked. 
 

sorry but that's all I can say. Mine works now and hasn't missed a beat since.