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February 2024 - email begins working, horrayhurray.
The addressFrom (letter label) must be manually configured for each letter - it defaults to “yourorganization.com” which is going to be filtered out as spam. The addressFrom address must be a valid Duke email. See https://knowledge.exlibrisgroup.com/Alma/Product_Documentation/010Alma_Online_Help_(English)/050Administration/050Configuring_General_Alma_Functions/070Configuring_Alma_Letters#Setting_the_From_Address
Erin enabled the setting separate_patron_notifications_by_library customer parameter for initial testing. This means that emails are split out to be sent from each library.
Each library needs an email address configured, and if the email address is marked to be used for “circulation communication”, then it will become the “from” address for the circulation letter, even if another address is hard-coded.
We may need to do further customization for letters such that if the letter is split out, that the “reply-to” email is set to that libraryother text is customized. See info at ~4:40 in
https://www.youtube.com/watch?v=Isn4c9O9K6E
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