OH4.0.0 Mail (Windows) - Could not convert socket to TLS

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1

Just switched my OH4.0.0-SNAPSHOT from RasPi4B+ (OpenHabian) to Windows 10. The RasPi was to bogged down. The response of the rules, GUI, etc. is way better on my windows machine. Regardless, the mail action worked flawlessly with OpenHabian but is throwing this error now. I have the Windows firewall currently disabled.

2023-06-08 17:11:24.881 [WARN ] [ab.binding.mail.internal.SMTPHandler] - javax.mail.MessagingException: Could not convert socket to TLS;
  nested exception is:
	javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
2

It is issue with trusting mail server certificate. The trusted certs are usually a combination of system and JVM level certificates. Apparently your mail server is not secured by a commonly used certificate authority and your operating system/jvm is missing custom CA.

3

One possible option you could try is to go into your Java settings inside the windows control panel and then under Java Control Panel Advanced and tweak those settings to get around some of those type of certificate validation checks as well as having it use the windows cert store to see if that helps.