After just over a year, a hard disk in one of the mini mail servers failed. The local IT guy had it replaced and reinstalled the system from the installer CD, after which he brought the machine back on-line. As soon as the machine booted, it also started all its services, meaning it started accepting mail. Unfortunately, the delta sync replication hadn't as yet caught up with a year of updates (!), so quite a number of messages bounced as the user accounts hadn't yet made it down the LDAP-pipe to the server. What should I have done differently? The installer CD-Rom should have disabled the Exim MTA until a human could intervene to check that the prerequisites for email reception were set up correctly.