Email notifications are not being sent while properly defined at the Uproc Level when having defined a "Customized email header"
In the universe.log, the following error appears when the email is supposed to be sent:
|ERROR|X|IO |pid=p.t| email_notification_build_ | o_io_email_subj_custom returned -1.
In the node settings section SMTP check if the values for the variables:
Customize email header
Known variables (such as UPR, SES, MU) should be introduced as !VARIABLE!
Release : 6.x
Component : DOLLAR UNIVERSE
Fix the value of the Customize email header, on the example above, replace !UPR by !UPR!