MIB seems to take a very long time to deliver email to outside destination

1

Using PHPMailer() in my web app, I send an email alert to a user through one of my MIAB accounts. It sometimes takes an hour or more before the user receives it in her Office365 hosted account.

I can see in my PHP logs that the email is sent (as far as my app is concerned) immediately.

I wonder if this is because of server time differences? The web app runs on UTC and MIAB is UTC+5.

Any other suggestions of where to look? MIAB is hosted on a DO Droplet if that matters.

2

Is PHPMailer setup to use MIAB postfix?

3

Did you ever resolve this? I’ve had similar issues (unresolved, hence coming to MIAB) with other web servers (on shared hosting). I think Office365 is rather aggressive about who it receives email from.