** 메일 계정 보안 설정 낮음으로 변경후 작업 1. build.gradle 추가 // mail compile("org.springframework.boot:spring-boot-starter-mail") compile "org.springframework:spring-context-support" compile "com.sun.mail:javax.mail 2. application.yaml 추가 mail: properties: mail: host: smtp.gmail.com port: 587 username: id password: pwd smtp: auth: true connectiontimeout: 5000 timeout: 5000 writetimeout: 5000 starttls: enable: ..