Purview DLP Blocks Sharing Files with Specific Domains or Users
A new DLP rule is available to control sharing of SharePoint and OneDrive files with selected domains and email addresses. The new rule supports an allow list (permit sharing) and can also specify a deny list (block sharing). The user interface takes a little getting used to, but when everything is configured and SharePoint has had a chance to respond to the block, the rule works and any attempt by a blocked user to use a sharing link is refused. https://office365itpros.com/2026/07/22/block-sharing-dlp-sharepoint/
Moving Office 365 Mailboxes to IMAP Servers - What’s the Best Approach
I’ve recently been looking into scenarios where organizations need to move mailboxes from Microsoft 365 to IMAP based email servers, and I noticed this is still a common requirement in many migrations. In most cases, the challenge is not just moving emails, but making sure everything like folder structure, old emails, and user data stays intact without creating too much disruption for users. From what I’ve seen, doing this manually can get very complex, especially when there are multiple mailboxes or large data volumes involved. That’s where migration tools usually come into the picture. Most tools simplify things by handling: 1. Secure connection to Microsoft 365 accounts 2. Bulk mailbox migration 3. Preserving folder hierarchy 4. Reducing downtime during the move 5. Avoiding duplicate data issues One thing I’ve noticed is that running a small pilot migration first always helps. It gives a clear idea of how the actual migration will behave before moving all users. Has anyone here worked on Office 365 to IMAP migration at scale? Would be good to know what approaches or tools worked best in your case and what challenges you faced during the process.Office 365 Mailbox Export to PST - Third Party Tools: What’s Your Experience?
Exporting Office 365 mailboxes to PST is still a common requirement in many Microsoft 365 environments, especially for backup, compliance, and migration scenarios. While Microsoft offers native options like Purview eDiscovery and Outlook export, many administrators also consider third-party tools when dealing with large mailboxes or bulk export requirements. In real-world scenarios, factors like speed, ease of use, permission handling, and consistency of exported data often influence the choice of tool. Some teams prefer native methods for compliance control, while others explore third-party solutions to simplify large-scale or repeated export tasks. For those working with Microsoft 365, what has your experience been with third-party PST export tools? Have they helped in your environment, or do you still rely mainly on Microsoft’s native options?Switching Data Loss Prevention Client-Side Checks for OWA
Purview Data Loss Prevention (DLP) rule checks can happen client-side and server-side. This change updates the Exchange Online organization configuration to instruct OWA to stop using Exchange Online to detect potential DLP rule violations before users send email. Instead, OWA will use the workload-neutral Data Classification Services (DCS). Using a workload-neutral service comes with some consequences in terms of OWA being unable to evaluate Exchange-specific predicates. https://office365itpros.com/2026/05/22/data-loss-prevention-dcs/DLP Extends Its Ability to Control Copilot Processing
A new action for the DLP Policy for Copilot allows Microsoft 365 tenants to block Copilot from performing (Bing) web searches if a prompt contains sensitive information types. The new action allows Copilot to continue to process prompts using Microsoft 365 content (if the user has a Microsoft 365 Copilot license) while stopping potentially sensitive data being sent to Bing. https://office365itpros.com/2026/04/16/dlp-policy-for-copilot-web/How to Test a File Against DLP Sensitive Information Types
Sensitive Information types (SITs) are definitions of data like credit card numbers used by DLP rules to detect potential external sharing violations. Knowing what SIT to use in a DLP rule is often difficult, which is why the Purview developers have added a test option to allow tenants to test files against individual SITs or all SITs to see what happens. https://office365itpros.com/2026/03/04/sensitive-information-type-test/Microsoft Extends DLP Policy for Copilot Protection to All Storage Locations
Microsoft has enhanced the DLP policy for Copilot to cover Office files held in any storage location instead of only Microsoft 365 locations like SharePoint Online and OneDrive for Business. The change is made in the Office augmentation loop, a little-known internal component that coordinates use of connected experiences by apps. Extending the DLP policy to cover all locations makes perfect sense. https://office365itpros.com/2026/02/24/dlp-policy-for-copilot-storage/Primer: How to Use RBAC for Applications to Control App Use of the Mail.Send Permission
The temptation to use the Mail.Send application permission in scripts can lead PowerShell developers into trouble because the permission allows access to all mailboxes, including sensitive executive and financial mailboxes. Fortunately, RBAC for Applications allows tenants to control the access that apps have to mailboxes and other Exchange content. All explained here with an example script to test RBAC of Applications. https://office365itpros.com/2026/02/17/mail-send-rbac-for-applications/
