Invoice Ninja still not sending after last patch

[AartJansen]

Haven't been able to send invoices this month. Queued tasks grows every time I try.
Mail settings were blank, but when I select to use SMTP nothing sends either

[joseph]

I guess this is a dup of https://forum.cloudron.io/topic/14264/unable-to-send-an-email-404-page-not-found-code-404 ? Let's continue the discussion there .