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By default, and if not opted-out, JEMHC will retain recent inbound email, allowing you to create a Test Case from the message received, to diagnose processing issues. From the Auditing > Inbound Messages screen, when retention is enabled, there is a Generate Test Case action:
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Importing a Test Case
Importing a Test Case allows to create a Test Case from a real email that has already been received. This is particularly useful when test a particular email that did not get processed correctly. Note: only txt and eml file formats are supported.
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