Microsoft have included spam-filtering in Exchange for many years, under the SmartScreen name. But from 1st November that will change: there’ll be no more updates and the feature won’t be included in new versions of Exchange Server.
Updates for SmartScreen client-side spam-filtering for Outlook on Windows will also be ending, although SmartScreen will remain current in Microsoft’s web browsers. Despite sharing the name the in-browser feature protects against malicious websites.
If you’re using SmartScreen now the existing definitions you have will still be there, and will still work, but there won’t be any more updates to them after 1st November.
The motivation for this seems to be twofold – the blunt instrument of applying a spam-confidence level to an email isn’t very effective, and Microsoft’s online protection offering does a far better job. Realtime filters can react faster to spoofed email, hijacked accounts, and user feedback. Coincidentally Exchange Online Protection is chargeable for on-premises users, perhaps as a further incentive to move to Office 365.
There is no net effect on Nexus from this change (Oxmail does the job of spam-scoring for the University) but, as many of you know, messages categorised as legitimate can still end up in ‘junk’ because of Outlook applying filters – it’s why we’ve always advised that users set spam filtering via the SCL and not via Outlook’s SmartScreen. The absence of future updates mean that client-side spam filtering will only become less effective over time.
In the longer term Nexus’ move to Office 365 should ensure that Exchange Online Protection has an opportunity to take over spam-filtering responsibilities.