spring.mail.host=smtp.qq.com
spring.mail.username=
spring.mail.password=
spring.mail.testConnection=false
spring.mail.properties.mail.smtp.ssl.enable=true
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.socketFactory.port=465
spring.mail.properties.mail.smtp.socketFactory.class=javax.net.ssl.SSLSocketFactory

spring.mail.host=smtp.qq.com
spring.mail.username=
spring.mail.password=
spring.mail.testConnection=false
spring.mail.properties.mail.smtp.starttls.enable=true
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.socketFactory.port=465
spring.mail.properties.mail.smtp.socketFactory.class=javax.net.ssl.SSLSocketFactory
spring.mail.properties.mail.smtp.socketFactory.fallback=false

Use tls and reject fallback
Use tls and reject fallback
