Office 365 Groups, transport rules, and network tweaks

Office 365 Groups, transport rules, and network tweaks

It’s been a busy week for many reasons, so I have a few things to report in quick succession.

First, a rather disturbing report emerged in Microsoft’s Office 365 Network on September 21 when Neil McCafferty reported that some Exchange transport rules configured in his tenant were being bypassed by messages sent to Office 365 Groups. This just didn’t seem right because all messages are supposed to flow through the transport pipeline so that they can be processed by rules. As I have documented, Clutter notifications are one exception that I don’t think should exist.

In any case, Neil wanted rules to stop users including profanities in their messages, so it was easy to test whether the case was as he reported. I was bemused to find that Office 365 Groups blithely ignored any restrictions placed by transport rules. Messages sent to a mixture of recipients were processed differently. Those sent to regular mailboxes were blocked while those directed to group mailboxes arrived, complete with any banned word you cared to include.

I also tested to see whether Data Loss Prevention (DLP) rules worked properly and once again found that you could send messages containing blocked sensitive data (like credit card or social security numbers) to group mailboxes. Clearly, some fundamental problem existed in the transport subsystem that caused traffic sent to group mailboxes to be handled differently (in a bad way) to regular mail. Fortunately, Microsoft agrees and is busy fixing the issue. Transport rules should work properly in the near future.

All of which poses the question of how this problem got through testing. Groups have been around for almost a year now and you would have thought that someone, somewhere (like in Microsoft software development) would have tested this functionality. But they didn’t. Or the test didn’t exercise the code properly.

On a more positive note, ExpressRoute is now available for Office 365 customers. You can watch an “Office Mechanics” video on YouTube to find out more. Basically, ExpressRoute provides a high-speed MPLS connection between your corporate network and Microsoft’s network so that Office 365 seems to be just another service available on the WAN. It’s expensive, but I imagine that this offering will be popular with larger enterprises who want to eliminate the Internet as a potential cause of SLA problems. Note that an Internet connection is still used for some services.

Speaking of networks, the nice people at Priasoft have done some interesting analysis of how Office 365 tenants connect to Microsoft’s network and how adjusting the DNS pointer to can speed connections for Exchange Online users. It’s worth reading so that you can test just how well your connections are doing.

On the podcast front, the Exchange Exposed podcast that Paul Robichaux and I do on a quarterly basis is evolving. We just taped our fifth episode, which you can find in the Apple iTunes Store. This episode, which was sponsored by Kemp Technologies covers recent happenings in the world of Exchange and Office 365, such as the imminent arrival of Exchange 2016. Given the amount of cloud content, we’re going to rename the podcast to be “Office 365 Exposed”.

I’ve been pleased at the reaction of readers to the launch of the second edition of “Office 365 for Exchange Professionals”. The new edition, which contains more than 150 pages of additional content over the May 2015 edition (which shows just how quickly things change inside Office 365), is available in PDF/EPUB format at and for Kindles at We update the book files regularly, so if you already have a copy, you might want to refresh the content from whatever site you purchased from to ensure that you have the latest. BTW, today is the last day that a discounted price is available for the PDF/EPUB books – tomorrow we revert to full price.

Lots of stuff is happening and there’s more to come. Stay tuned for what happens tomorrow.

Follow Tony @12Knocksinna

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