Some comments on ticket not generating email notification to reporter

[Glenn Taylor]

Multiple comments added by the same agent do not result in multiple email notifications to reporter. 
Instead, only the first comment added results in email.
Additional comments added by agent (within several minutes of each other) do not result in email to reporter. 

We need to resolve this, as important follow-up comments are not being communicated to the reporter. Thanks!

Steps to Recreate: 
Agent adds comment1 to ticket. 
Reporter receives email notification as expected. 

Agent adds comment2 to ticket.
Reporter DOES NOT receive email notification as expected. 

[Paul Krueger · Accepted solution]

The email handler batches messages in one-minute groups. I did some testing on our end and found that a one-off comment will generate a notification email almost instantly. Subsequent comments/actions were batched into 1-minute groups.

Have you confirmed your email client isn't grouping them into conversations and that any spam filtering isn't blocking based on rate-limiting or anything like that?

[Glenn Taylor]

There is nothing in our Exchange server that might be blocking or limiting emails. 
We did additional tests, and finding now that even comments added 24 hours apart are not being sent to the ticket reporter. 
A comment added by me on May 4 was emailed to the reporter. 
However, a comment added on May 5 was not emailed to the reporter. 
Very strange, any other ideas?   Thanks for your help so far!

[Glenn Taylor]

Thanks and mystery solved!
You were correct. When we checked 365 Defender/Quarantine last night, we noticed that some JIRA emails were being incorrectly marked as phishing, and held in quarantine. 
So no issue with JIRA at all, but rather with Microsoft. Your ideas helped a lot, thanks!

[Paul Krueger]

Great!

[Glenn Taylor]

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