Hello Maxime, In the spirit of assisting you, here are a few vectors to resolve your issue: Issue: "unable to find valid certification path to requested target at com.sun.mail.smtp.SMTPTransport.startTLS"
Suggestions: 1. OM configuration issue: Configure Admin -> Configuration Smtp_server: this is the smtp server to send messages. Smtp_port: this is the smtp server port normally 25 or 80, if using no SSL, otherwise 443 if using SSL encrypted e-mail. System_email_addr: all sent e-mails by the system including invitations will have this address: Email_username (System authentication email username): your e-mail's username: .... or on how your third party e-mail client is configured. Email_userpass: the password of your e-mail's username Mail.smtp.starttls.enable: 0 (if above 25 or 80) or 1 (if above is 443) Enable TLS 1=true, 0=false For example, in GMail, Smtp_server: smtp.gmail.com Smtp_port: Port 465 (SSL required) Port 587 (TLS required) 2. Additional: Firewall Open OS and software firewall SMTP ports. Set hardware firewall policies NAT allow from your server to WAN. Thank you. Sincerely, Hemant K. Sabat Coscend Communications Solutions www.Coscend.com ------------------------------------------------------------------ Real-time, Interactive Video Collaboration, Tele-healthcare, Tele-education, Telepresence Services, on the fly ------------------------------------------------------------------ CONFIDENTIALITY NOTICE: See 'Confidentiality Notice Regarding E-mail Messages from Coscend Communications Solutions' posted at: http://www.Coscend.com/Terms_and_Conditions.html -----Original Message----- From: maxime.gue...@bssp.fr [mailto:maxime.gue...@bssp.fr] Sent: Wednesday, July 12, 2017 12:29 PM To: user@openmeetings.apache.org Subject: help configuration smtp server Hello, We are installing a version of openmeetings (last stable) on a stretch Debian. Everything seems to work fine but we configured a smtp server with starttls port 587 from a functional mail server and we have a mail sending problem after creating a conference in the calendar. The "email Management" shows multiple errors as follows : Last Error 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 at com.sun.mail.smtp.SMTPTransport.startTLS(SMTPTransport.java:2064) at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:724) at javax.mail.Service.connect(Service.java:388) at javax.mail.Service.connect(Service.java:246) at javax.mail.Service.connect(Service.java:195) at javax.mail.Transport.send0(Transport.java:254) at javax.mail.Transport.send(Transport.java:124) at org.apache.openmeetings.core.mail.MailHandler$2.run(MailHandler.java:242) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:11 42) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:6 17) at java.lang.Thread.run(Thread.java:748) Caused by: 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 at sun.security.ssl.Alerts.getSSLException(Alerts.java:192) at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1949) at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:302) at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:296) at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:15 14) at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:216) at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1026) at sun.security.ssl.Handshaker.process_record(Handshaker.java:961) at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1062) at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:13 75) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1403) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1387) at com.sun.mail.util.SocketFetcher.configureSSLSocket(SocketFetcher.java:598) at com.sun.mail.util.SocketFetcher.startTLS(SocketFetcher.java:525) at com.sun.mail.smtp.SMTPTransport.startTLS(SMTPTransport.java:2059) ... 10 more Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:387) at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:292) at sun.security.validator.Validator.validate(Validator.java:260) at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324 ) at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java :229) at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImp l.java:124) at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:14 96) ... 20 more Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.j ava:141) at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBui lder.java:126) at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280) at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:382) ... 26 more Could you help us on configuring mail server with openmeetings ? Thanks for your help. Best Regards. Maxime --- This email has been checked for viruses by AVG. http://www.avg.com