It works with gmail.
First add the following line to /usr/local/Extreme_Networks/NetSight/appdata/NSJBoss.properties
mail.smtp.port=587
mail.smpt.auth=true
mail.smtp.starttls.enable=true
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Then login gmail account, disable to 2-step verification, and enable "Access for less secure apps"
Modify the NetSight E-Mail Server Option.
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Test the mail setting.
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It works~
Reference URL,
http://www.mkyong.com/java/javamail-api-sending-email-via-gmail-smtp-example/