Symptoms

Adding the flag -Datlassian.mail.senddisabled=true to the JVM should prevent JIRA to send any notification.  However, JIRA still sends emails.

Cause

Some JVM flags will not be read properly if there is a trailing space at the end of the flag.  Also, some particular applications require a separate line for each JVM flag.

Resolution

1. Use separate lines for each mail flag as some particular applications require to use a separate line for each JVM argument

2. If each JVM flag is separated by each new line, eliminate any trailing spaces after each flag.  In other words, make sure that there is no space after the flag -Datlassian.mail.senddisabled=true