I upgraded to build 416 and alas, Roon can’t find my core anymore (which resides on a QNAP server and is an older version as far as I can tell) - the upgrade made Roon completely defunct for me
Can I download the 401 build from somewhere, assuming that rolling back might fix the problem?
So we can better assist you, please provide a brief description of your current setup using this link as a guide.
Make sure to describe your network configuration/topology, including any networking hardware currently in use, so we can have a clear understanding of how your devices are communicating.
Since the update have you tried rebooting your Core machine?
Have you also updated your remote devices? Are all remotes unable to connect or just certain ones?