HPLIP cannot detect devices in your network...

[cadvanlei]

hello there,

the following error message pops up whenever (as far as I can see) I launch ImageScan! for Linux (Epson software):

HPLIP cannot detect devices in your network. This may be due to existing firewall settings blocking the required ports like (5353/udp). When you are in a trusted network environment, you may open the ports for network services like mdns and slp in the firewall. For detailed steps follow the link.

http://hplipopensource.com/node/375

the web address in the error message doesn't say anything about (k)ubuntu (?).
If it matters, I used sudo apt-get install hplip-gui to install HPLIP (and my printer works all right on Kubuntu 16.04).

what does the error message mean + how can i get rid of it?

thanks in advance.

[cadvanlei]

quick update: I removed hplip-gui - upon installing Kubuntu I didn't realise I don't need this as the HP printer is recognised automatically when i connect it via USB.
Now the error message is gone