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This guide describes troubleshooting options for notifications that it should've gone out based on the notification scheme and role of user ("Reporter") but they didn't receive it.
Outgoing mail is configurated under: Jira administrator: System > Mail > Outgoing mail
https://support.yamnet.com/secure/admin/OutgoingMailServers.jspa
Configuration of outgoing and incoming mail log is done under:
System > System support> Logging and profiling
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