CASE 1 Custom.properties conf.mailhandler.ntf_sndr_addr=user1@domainXX.com conf.mailhandler.email.domain=domainXX.com conf.mailhandler.mail.smtp.host=smtp.gmail.com:587 conf.mailhandler.mail.smtp.auth=true conf.mailhandler.mail.user=user1 conf.mailhandler.mail.transport.protocol=smtps conf.mailhandler.mail.smtp.starttls.enable=true conf.mailhandler.mail.smtp.starttls.required=false passwords.properties conf.password.SMTP=correctpassword Logs from JBoss 03:32:01,733 INFO [stdout] (Appian Work Item - 1 - ProcessExec00 : UnattendedJavaActivityRequest) 2017-11-07 03:32:01,731 [Appian Work Item - 1 - ProcessExec00 : UnattendedJavaActivityRequest] ERROR com.appiancorp.process.runtime.activities.SendEmailActivity - javax.mail.MessagingException: Could not connect to SMTP host: smtp.gmail.com, port: 587; Caused by: javax.mail.MessagingException: Could not connect to SMTP host: smtp.gmail.com, port: 587; nested exception is: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? CASE 2 Custom.properties conf.mailhandler.ntf_sndr_addr=user1@domainXX.com conf.mailhandler.email.domain=domainXX.com conf.mailhandler.mail.smtp.host=smtp.gmail.com:587 conf.mailhandler.mail.smtp.auth=true conf.mailhandler.mail.user=user1 conf.mailhandler.mail.transport.protocol=smtp conf.mailhandler.mail.smtp.starttls.enable=true conf.mailhandler.mail.smtp.starttls.required=true passwords.properties conf.password.SMTP=correctpassword Logs from JBoss 03:51:51,675 INFO [stdout] (Appian Work Item - 1 - ProcessExec02 : UnattendedJavaActivityRequest) 2017-11-07 03:51:51,675 [Appian Work Item - 1 - ProcessExec02 : UnattendedJavaActivityRequest] ERROR com.appiancorp.ap2.mail.Mail - Could not send mail via smtp.gmail.com:587 to userTo@gmail.com ...... 03:51:51,678 INFO [stdout] (Appian Work Item - 1 - ProcessExec02 : UnattendedJavaActivityRequest) 2017-11-07 03:51:51,677 [Appian Work Item - 1 - ProcessExec02 : UnattendedJavaActivityRequest] ERROR com.appiancorp.process.runtime.activities.SendEmailActivity - javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted. ......... Caused by: javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted. Learn more at 535 5.7.8 https://support.google.com/mail/?p=BadCredentials m9sm415570pff.26 - gsmtp