I've recently updated to the 1.4.0 OS and I'm having problems connecting too.

VNC from my desktop to Stellarmate works fine but connecting to the Web Manager works once or twice but then I am unable to access the web page.

I have tried opening the web page locally from the StellarMate desktop (via VNC) . This returns "This site cannot be reached. localhost refused to connect. ERR_CONNECTION_REFUSED" web page.
I get the same response if I try from a browser on my desktop using the StellarMate local IP address (192.168.1.4 on my network - this is static, assigned by my router)

It seems the upgrade to 1.4.0 has broken some of the connections and I'm left wondering if this relates to the 8624 port since port 5900 is ok for VNC.

Not sure any of this will help you with your problem but you're not alone with problems after upgrading.
I'm thinking of going back to 1.3.5 for the time being.

Chris

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