I currently have Invoice Ninja self-hosted on one server and use another server for emails. In Invoice Ninja I have the details of the email account set-up as SMTP. I noticed that my clients often do not receive my invoices but do receive my regular emails.
I sent a test email from IN to mail-tester.com and the results (8/10) are different than those from my regular email (10/10):
It seems to be a problem with SPF and the return address but I cannot figure out what I am doing wrong.
If anyone could shed some light on this I would be really grateful.