X1 does not launch -- "Connecting to Index Service"

All was working well for a few days with latest X1 Search 8 Beta, until yesterday when after "Loading Plug-ins" on launch, I get the message:
"Connecting to Index Service"
which it never does. I see X1ServiceHost.exe is running in Task Manager and the X1 service appears to be started in "Windows Services". I looked in the X1 log and I can not find that the X1 service has crashed.

What can I do to fix this error?

Thanks,
Tom D.

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