Hi All,
We have an on premises server hosting 6 domain names. 4 of these work perfectly for send receive however 2 (the same 2) will not send with mail stuck in the queue but will receive.
The 2 that will not send and are stuck in the queue get error 452 which is usually due to resources however all resources are fine. We have checked the domains to ensure they are not on any block lists etc.
The 6 domains have worked perfectly for over 18 months and the 2 that started to fail to send both failed at around the same time.
There are no issues we can see in the event viewer.
Can anyone shed any light on where else we can look...???
Many thanks.
