We have checked known settings that control email notifications within LMS and setting mirror those in TEST but no email notifications are being sent from Learning.
Support tested and could see notifications being generated and we could receive notifications without issues, it turns out only the customer could not.
Learning Management System (LMS)
I have heard back from our internal IT department who can see that notifications are becoming stuck in our mimecast server.
Support provided customer's LMS IP addresses for whitelist but that still did not resolve the issue.
Therefore the following was suggested by Operations:
The customers mail administrator need to add SF outgoing ip list to their spf record with the include parm.
v=spf1 include:_spf-sfdc.successfactors.com ~all
It will contain the actual list of outgoing IPs.
notifications, mail server, SMTP, SPF, email, mimecast server , KBA , LOD-SF-LMS-ADM , Admin Tools , LOD-SF-LMS , SuccessFactors Learning , Problem