Using MacBook Pro M3, macOS Tahoe 26.4 as Roon Core In Roon>Settings>Roon ARC, Message: "Not Ready, Roon ARC will not be able to access your Roon Server. Roon ARC was unable to securely access your Roon Server. Please ensure UPnP is enabled on all routers so Roon can automatically configure your network for ARC."
Diagnostics data for Roon Support: { "ipv4_connectivity": {"status":"NetworkError","status_code":504,"error":"error code: 504"}, "ipv6_connectivity": {"status":"NetworkError","status_code":504,"error":"error code: 504"}, "external_ip": {"actual_external_ip":"24.aaa.bbb.ccc","actual_external_ipv6":"2601:ddd:eee:fff:ggg:hhh:iii:jjj","router_external_ip":"null"}, "natpmp_autoconfig": {"status":"NotFound"}, "upnp_autoconfig": {"status":"NotFound"}, "multinat_autoconfig": {"status":"Failed","error":"No uPnP Routers found on LAN"} }
On iPhone 16, iOS 26.4, roon ARC app:
Roon Server last seen less than a minute ago, red X "Not accessible outside of your network. To connect, make sure your Roon Server is turned on and configured for remote access.
MacBook Pro is connected to router via ethernet. Router is Comcast Xfinity. They have switched admin functions to their XFINITY app, and I didn't see any references to UPnP on the app.
Tell us about your home network
· Router is Xfinity supplied router, no model number visible. no switches or extenders. No VPN
Looking at your diagnostics, the error “No uPnP Routers found on LAN” is the clear culprit. While your Xfinity router is seeing your MacBook, it isn’t “talking” to Roon to open the necessary port for ARC.
You are exactly right—Comcast has moved almost all “advanced” settings into the Xfinity app, and they have actually disabled the ability to toggle uPnP on many of their newer gateways for security reasons. Because of this, Roon cannot automatically configure the connection.
Since uPnP isn’t an option, you’ll need to set up a Manual Port Forward in the Xfinity app. It sounds technical, but it’s just three steps:
Open the Xfinity App: Go to WiFi > View WiFi details > Advanced settings > Port Forwarding.
Select your MacBook Pro: Choose your M3 MacBook from the list of connected devices.
Enter the Details:
Internal / External Port: 55000 (This is the default Roon port).
Protocol: TCP (or TCP/UDP if “Both” is an option).
Save/Apply.
Since you are on macOS Tahoe, even if the router is set up correctly, the Mac itself might be “ghosting” the connection.
Go to System Settings > Network > Firewall.
Click Options and ensure that Roon and RoonApp are set to “Allow incoming connections”.
Crucial: Ensure “Block all incoming connections” is OFF.
Please give the Port Forwarding a try and let me know if it clears that 504 error!
