Emails suddenly not working - creating issues & notifications

[Lindsay Donaldson]

We have been using Jira Service Desk for a a few years, and had it set up to create issues from emails sent to our IT desk email. It was also set up to send email notifications to users (upon us accepting the ticket, closing the ticket and any correspondence). However, one day this suddenly stopped working.

I have checked various settings, and logs including debugs. We receive the test emails the system can send. The system also says that it's receiving our test emails and creating issues but these are not being created. Also any comments/replies sent via email are not being attached the issue at all (not even to the wrong issue). We are receiving notifications that we are about to breach SLAs and also to advise the user on the SLA for their issue once we have accepted it. However no correspondence is getting through - if we comment no email is received.

Passwords haven't changed - we use server based exchange for our emails. We can also create issues as usual and any issues created via our Support Portal are coming through as well. I have restarted the service, as well as restarting the whole server Jira is installed onto. I re-indexed just in case. We are on version 7.12.3.

Does anyone have any suggestions on how we can fix this?