For some reason I can't send e-mails anymore. My mail provider didnt changed a things, so it'll be probably because of Jira? This is the error of test email:
An error has occurred with sending the test email:
com.atlassian.mail.MailException: javax.mail.MessagingException: Could not convert socket to TLS;
nested exception is:
javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target