Some e-mail that is send to our exchange 2013 server is delivered with a lot of delay (like 15 minutes).
A message was sent to 3 e-mail addresses, of those, 2 people received the e-mail without delay, but only one person had 15 minutes delay. All 3 mailboxes are on the same Exchange server, to the issue is probably something internally.
When I check the logs, I see 'HAREDIRECTFAIL' (no suitable shadow servers). We didn't configure exchange in HA mode.
Anyone has any pointers on where to look?