Can Microsoft 365 Copilot Access Archive Mailboxes?
After writing about the new 100GB mailbox quota for Microsoft 365 Business Tenants, I was asked if Microsoft 365 Copilot supports Exchange Online archive mailboxes. It does. Microsoft Search indexes items in archive mailboxes, so Copilot can find and use items from those mailboxes. Interestingly, the DLP policy to block external email for Copilot didn’t work. That’s definitely something to investigate! https://office365itpros.com/2026/10/08/archive-mailbox-copilot/Using the Exchange Import-Export Graph API to Access Group Mailboxes
After saying that the Graph didn’t offer much support for group mailboxes, I was promptly countered with an article explaining how to use the Exchange Import-Export API to access folders and items in group mailboxes that wasn’t limited to just the Inbox. Well, the good news is that the approach works, as seen in a complete script written to prove the case, but whether I would ever use this API for a purpose it was never designed for is quite another matter. https://office365itpros.com/2026/10/07/group-mailbox-folder-items/
Unable to Open an Old OST File After Outlook Profile or Mailbox Changes
Hi everyone, I am looking for suggestions on handling an old OST file where the original Outlook profile or mailbox is no longer available. The situation is that an OST file contains important mailbox data, but Outlook cannot open it normally after changes to the user account or profile. This can happen after a Microsoft 365 mailbox change, Exchange migration, user account removal, or when an OST file becomes damaged. Since OST files are linked to the Outlook profile and mailbox that created them, simply moving the file to another system does not always make the data accessible. Before attempting any recovery approach, I would like to understand the recommended steps: Is there any Microsoft-recommended method to access an orphaned OST file? What checks should be performed before trying to recover data from the OST? How do administrators usually handle old OST files when the original mailbox is no longer available? What is the best way to validate recovered mailbox data? I would appreciate feedback from anyone who has handled similar Outlook OST recovery scenarios after Microsoft 365 or Exchange changes.How to Recover Data from a Damaged or Corrupted OST File When Outlook Cannot Open It
Hi everyone, I have seen several cases where users still have an old OST file but cannot access the mailbox data inside it. This usually happens after an Outlook profile is removed, a Microsoft 365 or Exchange account is changed, a mailbox is no longer available, or the OST file becomes damaged or corrupted. One common misunderstanding is that an OST file can be opened on another computer in the same way as a PST file. However, an OST file is linked to the Outlook profile and mailbox that created it. If that connection is no longer available, Outlook may not be able to open the file normally. Before trying to recover the OST data, it is worth checking a few things: Is the original Microsoft 365 or Exchange mailbox still available? Can the Outlook profile be recreated and synchronized again? Is the issue related to the OST file itself or only the Outlook profile? Do you need the complete mailbox data or only specific folders/items? If the mailbox is still available, rebuilding the Outlook profile and allowing Outlook to create a new OST may be the better approach. However, if the mailbox no longer exists, the Outlook profile has been deleted, or the OST file is damaged and contains the only available copy of the mailbox data, recovery becomes a different process. In these situations, it is important to first check what information is still readable from the OST file. Scanning and previewing the mailbox data before export can help identify available folders, emails, attachments, contacts, and calendar items before creating a new PST file. A practical OST recovery workflow usually involves: Keeping a copy of the original OST file before making any changes. Checking whether the original mailbox can still be synchronized. Scanning the OST file to identify available mailbox items. Reviewing important folders and messages. Exporting the required data to PST. Validating the resulting PST in Outlook. A detailed overview of the OST to PST conversion process, including scanning, previewing, selecting mailbox items, and exporting recoverable data, is available here: https://www.edbmails.com/pages/ost-to-pst-converter.html One important point to remember is that recovery results depend on the condition and readability of the OST file. A conversion tool can help extract available mailbox information, but it cannot recreate data that is no longer present or readable inside the source file.How to Update Teams Settings After Transferring Meetings
When discussing the transfer ownership of calendar events, we pointed out the Teams meeting problem. Essentially, if an event is a Teams meeting, details of the online meeting are not updated to allow the new owner to control its settings. The result is that recordings and other online meeting artifacts can end up in the wrong place. Microsoft should fix the problem. In the meantime, a PowerShell script illustrates the issue and shows how a fix might work. https://office365itpros.com/2026/08/25/teams-meeting-transfer/How to Use JSON Batching to Permanently Remove Mailbox Items
Following up on the primer explaining how to use JSON batching, this article expands on the principles explored in the primer and explains how to permanently remove batches of mailbox items. Removing mailbox items requires more care and attention than updating some Entra ID user accounts, and we explain what the batch commands are to effect both permanent and recoverable deletions. A full working script is available for you to try out. https://office365itpros.com/2026/08/17/json-batching-mailbox-items/How to Bulk Transfer Meeting Ownership Between Mailboxes
The Invoke-ChangeMeetingOrganizer cmdlet can transfer meeting ownership from one user to another. In this article, we discuss using a PowerShell script to transfer meetings in bulk between users. The code requires a mixture of Exchange Online and the Microsoft Graph using a registered Entra ID app. It all sounds complicated, but really isn’t – and the code handles scenarios like transferring meetings from someone leaving the organization. https://office365itpros.com/2026/08/10/invoke-changemeetingorganizer-bulk/Use the Invoke-ChangeMeetingOrganizer Cmdlet to Transfer Meeting Ownership
The Invoke-ChangeMeetingOrganizer cmdlet transfers meetings from one organizer to another and makes sure that all calendar settings are preserved. All of which sounds good, but some limitations exist that you should be aware of. The most important limitation is that although Exchange Online can switch ownership for a meeting event, it does nothing to update any online component, like a Teams meeting join URL. That remains a manual task. https://office365itpros.com/2026/08/06/invoke-changemeetingorganizer/
Google Workspace sender stuck at SCL=5 to all Microsoft-hosted recipients
Sending email from a new domain via Google Workspace. All mail to Microsoft-hosted recipients (both Outlook.com consumer accounts and Microsoft 365 Exchange Online tenants) is being routed to junk. Authentication passes perfectly on every message. This appears to be a domain reputation cold-start issue and I am looking for guidance on how to resolve it without waiting 2-4 weeks. Affected recipients are all Microsoft-hosted recipients tested (Outlook.com consumer + Microsoft 365 Exchange Online tenants). Please help me!!! Confirmed via X-MS-Exchange-Organization-SCL: 5 and delivery header dest:J;OFR:SpamFilterAuthJ;RF:JunkEmail on all test emails including ones with normal subject lines and body text. Content makes zero difference to the score. What has already been done: SPF hardened from ~all to -all DMARC upgraded from p=none to p=quarantine IP confirmed not listed on Microsoft's delist portal (sender.office.com) Domain confirmed not listed on Spamhaus DBL or SURBL Domain registered with Google Postmaster Tools JMRP enrollment attempted — not available to Google Workspace senders as SNDS requires IP ownership Outlook.com Postmaster support request submitted
Techcommunity Follow email notification no longer working
Hello, Not sure if this is the right place to post this issue but I could not find another method to report this issue.. As an Exchange Admin in our invironment it's very usefull to stay up to date on the latest new posted in a variety of blogs on this website (Exchange Blog, M365 Blog, ...) This all went well until a few months ago where I started noticing I didn't receive any weekly updates anymore regarding new blogposts & tried to manually go check periodically, thinking it would be a temporary system. After investigation i've noticed that i'm not the only admin in our company that no longer receives these emails from mailto:email address removed for privacy reasons So I wonder if something bigger is up or if it's only my company being affected, not receiving these follow notifications anymore? Is there any other way that I should report this issue, to those managing this website so it can be investigated in detail if it's only us? Already tried to unfollow/delete follows in my profile - save - follow again, same on the respective blog pages, but this does not seem to change anything.
