Who this is for: Staff using the Cannon VoIP app, Wi-Fi phones or cordless handsets on a guest or isolated Wi-Fi network.

What goes wrong

Why it happens

Guest networks and client isolation keep devices on Wi-Fi from talking to each other, and sometimes limit what they can reach on the internet.

That's good for visitors, but it can block phones from reaching local equipment, and some guest networks also block the ports calls use.

Put staff phones and devices on your main staff Wi-Fi, not the guest network.
If phones must be on a separate network, make one just for phones (a voice network) without client isolation.
Make sure the phone network allows the outbound ports listed on the firewall page.
If phones need to reach local equipment (paging adapters, door phones, intercoms), keep them on the same network as that equipment, or allow traffic between the two networks.
Save and reconnect the phones to the network.

On most home and small office routers, look under Wireless > Guest Network for "Allow guests to see each other and access my local network" or similar.
On most business Wi-Fi systems, look in the SSID settings for Client Isolation, AP Isolation, Station Isolation or Layer 2 Isolation, and turn it off on the network the phones use.
Some guest networks also limit time or bandwidth per device. Check those limits if calls drop after a set time.

Make a call from the app on the network the phones use. Audio is clear both ways.
Wi-Fi phones can page through the paging adapter or reach the door phone.
Run the free Net Checker while connected to that network.

Still having trouble? Contact Cannon VoIP support at 888-973-0515 or support@cannonvoip.com.