Recurring editor and delivery failures.
Email Builder issues
What is broken?
Unlink and resend when needed
Confirm Settings API key via GET /connection. Check Automatically send on publish. If that setting is off, publish does not send — use Send to Mailchimp. If auto-send failed, use Send to Mailchimp. If the remote campaign is gone, Unlink from Mailchimp then Send to Mailchimp. update-draft only works while Mailchimp status is save.
Check delivery mode and migration flags
Migrated NGL archives (Migration::is_migrated) are read-only for Mailchimp and Engagement. Dynamic system emails use the post slug as the key. Bulk Mandrill sends need a prc_email_audience_* list.
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Mailchimp send missing after publish
Check Newsletters → Settings. If Automatically send on publish is off, publish does not create or send the Mailchimp campaign — use Send to Mailchimp on a published, non-migrated campaign. If auto-send is on and still failed, use the same control. If the remote campaign is gone, Unlink from Mailchimp (clears local linkage meta only), then send again. Confirm audience/segment still match.
Update Mailchimp draft returns 409
The linked campaign is not in save (draft) status, audience/segment mismatch, or HTML cannot render. Sent or scheduled campaigns cannot be updated this way.
Engagement panel missing
Migrated archive posts skip Engagement. Campaigns need a linked Mailchimp send and report sync (report/refresh or the daily Action Scheduler job). Mandrill transactional emails show Engagement after CRM is active and prc_email_delivery_mode is mandrill. Refresh rereads CRM events. It does not use Mailchimp campaign reports.
Connection or audiences empty
Check Newsletters → Settings for the Mailchimp API key. GET /prc-email-builder/v1/connection reports connection health for the sidebar.