Trying to set up Sparkpost for Civicrm 5.12.0 / WP 5.1.1 / php 7.2
I was trying the cividesk extension but I'm on the EU server and can't figure out the fiddling needed to access that just yet.
So I've tried setting up smtp. I've configured Admin > Settings > Outbound mail and got a confirmation note from Sparkpost that it works. However, that test email hasn't been subsequently sent - Sparkpost has it as 'accepted' but not gone anywhere.
As advised by Sparkmail - I've set up mail.digilocal.org.uk as my mail subdomain. The sending DNS checks have been verified (DKIM / bounces).
I've tried sending a bulk email (just to myself but using a test group) with the following bounce report:
authentication failure [SMTP: Invalid response code received from SMTP server while sending email. This is often caused by a misconfiguration in Outbound Email settings. Please verify the settings at Administer CiviCRM >> Global Settings >> Outbound Ema
I have a FROM email address email@example.com and have set up a mailbox on my domain with that address. I've also set it up as the default bounce address (which is I guess how I'm getting the report).
I've got two other installations of civicrm working and not had these issues. Not quite sure what's so different with this domain.