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Catch Email Address
This value defines a Email an incoming mailbox Address that must be found within from the recipients of the email in order to be processed by JEMH.
If left unspecified then JEMH will not know your Mailbox to address and will not filter from being added to the issue, which can cause mail loops.
See the following for info about Mail Loops: How to prevent Mail Loops
Also if unspecified then this will mean that all emails will be processed even if they do not contain a Catch Email Address.
Catchemail addresses must not match Profile > Notification > Forward User/email as this causes a mail loop, entering a match will result in an edit time error:
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Catch Email Headers
CSV list of Email Headers that JEMH should check for a Catch Email Address within.
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