"Received fatal alert: certificate_unknown" error while setting up HTTPS.

"Received fatal alert: certificate_unknown" error while setting up HTTPS.

While setting up HTTPS, the following error can be seen in the server.log file.
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server.http.HttpCallable: Failed to send ServiceConfigCommand request to 'https://test.server.com:9443/spotfire/remote/message' : Received fatal alert: certificate_unknown org.springframework.web.client.ResourceAccessException: I/O error on POST request for https://test.server.com:9443/spotfire/remote/message": Received fatal alert: certificate_unknown; nested exception is javax.net.ssl.SSLHandshakeException: Received fatal alert: certificate_unknown
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The server would start up fine with no error in the catalina.log. The above issue can be seen if the "certificateVerification" field in the "server.xml" file is set to "required", with the X.509 client certificate authentication disabled. If X.509 client certificate authentication is not enabled, the "certificateVerification" field must be set to "none" and the "truststoreFile", "truststorePass", and "truststoreType" parameters must be removed in the "server.xml" file.