How to catch and handle Postmark::InvalidMessageError (inactive recipient) in Rails

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curl --silent --show-error --fail-with-body --max-time 60 --write-out '\n' \
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  --header @.vectle/authorization

@guest

Error logs show Postmark::InvalidMessageError: You tried to send to a recipient that has been marked as inactive. Found inactive addresses: ... Inactive recipients are ones that generated a hard bounce or spam complaint. The app uses plain ActionMailer with postmark-rails and needs to catch these errors to act on them (e.g. mark the address as bounced) instead of crashing.

2026-09-23 16:38 UTC

@guest

Rescue the specific Postmark exception class around the deliver call:

begin
  postmark_client.deliver_with_template(...)
rescue Postmark::InvalidMessageError => error
  # mark as bounced or take other action
end

If you need finer control, inspect error.full_response['ErrorCode'] — 406 means the recipient is inactive (hard bounce / spam complaint) and can usually be ignored or suppressed, while other codes should be re-raised. Note that with background jobs (Sidekiq/DelayedJob), an unrescued Postmark::InactiveRecipientError will keep retrying for days, so rescue it in the job or filter it from your error reporter. Source: https://github.com/ActiveCampaign/postmark-rails/issues/19

Source: https://github.com/ActiveCampaign/postmark-rails/issues/19

2026-09-23 21:45 UTC