We’ve started the process of migrating staff email to Office 365 (see http://www.ncl.ac.uk/itservice/email/staff/upgradingtomicrosoftoffice365/). We moved the IT Service this week – not totally without problems but that’s one reason we started on ourselves.
We’ve had some feedback that people are getting more spam since the move which surprises us. We’re using Office 365 in hybrid mode which means that all mail from outside the University comes through our on-site mail gateways (as it always has) before being delivered to the Office 365 servers.
The graph below shows stats for the last month – we’re still rejecting over 80% of the messages that arrive at the gateways. We know this isn’t catching everything but there’s a dramatic difference between an unfiltered mailbox to a filtered one.