[Lancaster] Firewall problem

[Ken Hough]

Hi guys, long time no meet/talk.

I need some help wrt firewall settings.

My main PC (Core 2 Quad Q9550 with 8GB RAM) runs Debian Jessie, I use Firefox, 
KMail, etc with iptables configued via gufw. No problems.

I recently set up my Canon Pixma MG5650 printer/scanner to operate via wifi 
which it does correctly provided that the firewall is disabled. I've tried 
various firewall settings that I've seen recommended via the Internet, but 
without success.

Can any of you gurus help me?

Ken Hough
Kendal