Hi @Peter-DG ,
It looks like your non-Meraki switch is manageable because it has an IP address within VLAN49 IP address range.
I suspect your non-Meraki switch has the port connecting to your Meraki switch configured as Trunk, Native VLAN = 49 and Allowed VLANs = 49 and 50. Probably you have the port connecting to your MR Access Point (AP)configure the same.
Therefore, check if you non-Meraki Switch has a configuration interface. Usually, you just put the switch IP on your web browser. I assume you have the administrator password.
Then, make sure you non-Meraki Switch has all the three VLANs associated with your SSIDs. Finally, configure the Trunk ports connecting to your MEraki Switch and to your AP as Trunk, Native VLAN = 49, Allowed VLANs = (all three VLANs).
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