one of our jobs that sends out daily emails to a bunch of users has slowed down and stopped over the last couple of weeks. Out infrastructure team rebooted the server as on the day it was showing a lot of errors on mail it was a day they had update issues.
REbooted and it seemed to clear the emails sending out over 600 queued emails. Now I had a quick peak at it today and it seems to be giving an error that it has been giving on and off for a while, that is that emails cannot be sent as the process requires a valid recipient.
I've checked the SQL for this and it Returns a pile of user emails. Yet when I run the SQL from the job, it comes up with a message for each recipient that says "email queued", an the DB log shows failed to send. I've also got the log file open and it won't shut, it seems frozen. I discovered when you tick maintenance plans box and then click stop it just hangs saying cancel pending in the bottom left of log file viewer screen.
Can anyone shed what might be causing these issues?