Failed to communicate with "/interface-data/init? Network Error?

I initially was able to connect to my new calibre web server... after a couple of days I have been getting this error...

First I get this...

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Then this...

"Failed to communicate with "/interface-data/init?1517366688958", network error, is the server running and accessible?"

Server is up and running... tried various things and still same error. No look googling or searching forums...

Bill