Exchange Online

Anticipating Microsoft Ignite 2020

by Tony Redmond

Welcome to 48 Hours of Free Technical Content The annual Microsoft Ignite conference for IT Professionals was originally planned to run in New Orleans starting today. Due to the Covid-19 pandemic, Microsoft decided not to run in-person events through June 2021, and consequently Ignite 2020 is now a 48-hour online event run over three days… Read More

What’s the Real Size of Exchange Online Mailboxes?

with 1 Comment by Tony Redmond

The Office 365 Substrate uses Exchange Online mailboxes to store a lot of data that users never see. The data is used by the substrate for different purposes, mostly to make it easier for features to get to relevant information. Microsoft doesn't document exactly what is stored, where it is stored, and how it is used, so we must poke around in the innards of mailboxes to see what we can discover.

How Exchange Online Processes Journal Reports for Protected Email

by Tony Redmond

Office 365 tenants often want to journal email from Exchange Online mailboxes. Things become a little more complicated when protected email is involved, but Exchange can decrypt protected messages and create journal reports with attachments containing the original encrypted message and a decrypted copy. That should be enough for journaling systems to process the journal reports and import messages into their repositories.

Stop OWA Users Autoforwarding Email

by Tony Redmond

Autoforwarding is Badness Allowing users to forward their email outside Exchange Online is bad, especially if they don’t keep a copy of the forwarded messages in their mailbox. Apart from removing email from the controls imposed by data governance policies, it creates a risk that confidential information travels outside the organization, including when an attacker… Read More

Purging Unwanted Messages from Exchange Online Mailboxes

by Tony Redmond

Microsoft will remove the Search-Mailbox cmdlet from Exchange Online on July 1, but that doesn't mean you can't purge bad messages from user mailboxes. Office 365 content searches and content search actions can hard- or soft-delete messages. Some limitations exist, but not enough to be worried. And we include a PowerShell script to show how to get the job done.

Microsoft Working on Outlook Cloud Signatures

with 2 Comments by Tony Redmond

The news that Microsoft is working on cloud signatures for Outlook for Windows is welcome. The venerable Outlook client has long stored its signature information in the system registry, which makes it hard to move signatures from PC to PC. On the other hand, OWA stores its signatures in mailboxes, so the same signature is used no matter where you log in. Of course, OWA is a simpler client (no profiles, for instance), but it should be eminently possible to store everything Outlook needs in the cloud. At least for Outlook clients connected to Exchange Online...

Microsoft Closes Outlook Copy-On-Write Flaw with Exchange Online Fix

by Tony Redmond

Microsoft fixed the copy-on-write bug in Outlook for Windows in Exchange Online. The fix stops users removing attachments from sent or received messages. A strong case can be made that the fix should have been present from the start to stop any possibility that clients could comprise Exchange Native Data Protection. Microsoft doesn't think many people were affected and they could be right, but that doesn't make the problem any easier to swallow.

Outlook Flaw Compromises Exchange Online Native Data Protection

by Tony Redmond

A bug in Outlook desktop's implementation of the MAPI over HTTP protocol allows users whose mailboxes are on hold to remove attachments from messages. The removal is not captured by the copy-on-write feature of Exchange Online Native Data Protection, which potentially compromises the ability of Data Governance managers or eDiscovery investigators to recover information needed for compliance purposes. All in all, it's a mess that Microsoft needs to clean up quickly.