Anti-Virus blocking scanner ports?

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I have a Canon Pixma mutli-function printer/scanner connected via WiFi. It worked fine with my previous system running Windows Vista, but on my new Win8.1 system, the scanner says it can't talk to the computer. I can print with no problem.
I'm using Avast Pro Anti-virus 2015.10.0.2208, and Windows firewall. I verified that the firewall is set to allow the Canon IJ network utility to pass through.
Canon support says (here goes the finger-pointing) that the anti-virus must be blocking the ports the scanner uses. Is that possible, and if so, how do I tell Avast AV to allow the communication? The following ports are used:
TCP 80
TCP / UDP 8611
TCP / UDP 8612
TCP / UDP 8613

[Pondus]

Right click avast tray icon and pause shields ..... does it work then?

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On Win7(64bit)  I don't know windows firewall. I can comment from what Outpost needed to permit, and it's almost identical to what's in Kerio on XP for Pixma printer/scanner.

WIAWOW64.exe
- udp in/out, remote IP of printer, ports 8611-8614
- tcp out, remote IP and ports as above
or just allow wiawow64 out to lan over udp and tcp
SVCHOST.exe
- udp out, remote IP and ports as above

On win7 for printer:
SPOOLSVC.exe
- udp broadcast out, remote 255.255.255.255, port 8611-8614
- tcp out, remote IP of printer, ports 8611-8614
- udp in and out, remote IP and ports as above

On XP I also needed to allow Netbios broadcast by
SYSTEM
- UDP out, remote broadcast ip such as 192.168.1.255 or whatever your LAN IP is. I suspect on Win7 svchost takes care of it.

That's for ethernet cable connected printer. WiFi should not be different.
If you don't use static IPs, then replace the printer IP with the LAN range.

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Right click avast tray icon and pause shields ..... does it work then?

Ah, good suggestion. It makes no difference, so the problem is elsewhere. I'll get back to Canon.