My host seemingly did something to their settings last week, and suddenly any attempt to send via mandrill times out and creates an entry in the error log.
Initially I was told by my host this is because they had blocked all ports, except ones requested to be opened by customers. However, I have since been told that the standard ports (25, 587) are wide open and the fact I can still send emails via PHP Sendmail demonstrates this.
They are telling me Xenforo must be trying to connect via a non-standard port.
Can anyone advise whether this is the case?