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If you downloaded JIRA Client without bundled Java, or run it with .bat / .sh script, then you probably should know which Java does JIRA Client use, or you can find out by inspecting your PATH and JAVA_HOME variables.
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Locate cacerts Key Store File
The location of cacerts is jreHome/lib/security/cacerts, where jreHome is the home path of the JRE in use. (Note that if you're using a JDK, then jreHome would be jdkHome/jre.)
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