NETGEAR Orbi 850 Series mesh Wi-Fi keeps disconnecting

The checks in more detail

Owners on NETGEAR's community report drops after firmware updates and note that devices dropped intermittently with a signal bar that looked fine, and NETGEAR's advisory on auto-update problems for the 850 series applies, so check the firmware version and update manually. Restart the system. Some devices cling to a distant unit, so toggle their Wi-Fi to reconnect near the closer one. Interference from neighbors can cause evening drops. Update the device's own drivers. Turn off Smart Connect to test whether band steering is involved by giving the bands different names. If one satellite drops repeatedly in a good spot, it may be faulty.

Record when drops happen, since a drop at a fixed time points to a scheduled restart or a router update, and drops at evenings point to interference or load. A router log on orbilogin.com under Advanced, Administration, Logs records the events and shows whether a satellite disconnected or the internet link failed, which tells you which part to fix first. If drops started after the router's auto-update, the advisory for the 750, 840 and 850 series explains the auto-update fault and how to recover, and following it, rather than resetting at random, avoids losing your configuration.

After recovering, disable automatic updates until you have read the next release's notes. A last check is the Orbi's wireless channel and the router's Wi-Fi settings for 160 MHz channel width on 5 GHz, which can be unstable in crowded areas; setting the width to 80 MHz often steadies a network that drops under neighbors' interference. Change one setting at a time and give it a day to see the result.