Moving Exchange Account Source Account
I have a very complex environment I'm hoping someone might jump start my search. We have two domains syncing to Entra ID. One domain is a resource forest where our Exchange environment sits. That domain contains disabled stub accounts synced to our primary domain where the actual user accounts sit. The source for all EXO mailboxes are the stubs in the resource forest. Those accounts are kept in sync using FIM 2008. We're wanting to decom that entire resource environment and move all of the attributes to the primary domain. The resource domain schema is the last version of Ex 2016. The primary domain schema is Ex 2010 SP1. I know my first step is to update the primary schema, however, has anyone encountered a situation like this? Any help would be greatly appreciated.
Replying to emails from M365 Outlook group
A problem I am stumped with, so I am reaching out for some help/guidance. One group wants to not have the emails going into their own inbox but manage and reply only from the group inbox itself (so they know the email has been processed by deleting it once replied). It worked OK to begin with and then some users couldn't reply, then more. Some still can. I have tried reindexing local copy, using browser instead of app & changing the send on behalf of permissions. Owner or member of group doesn't seem to make a difference. Error messages include "This message can't be sent because it no longer exists. It can only be discarded. Make sure you copy the contents of the message before you discard if you want to use them later." and "Couldn't send this message". Please see screenshots attached. My questions: 1: Is Outlook on M365 designed to allow users to reply from the group either as the "group" or as themselves? Information I found isn't clear. 2: If it is / can be - what can I do to make it work for all users? Thanks!How to Check if Shared Mailboxes Need MDO Licenses
Shared mailboxes might need Microsoft Defender for Office 365 licenses, but how do you identify how many licenses? We use PowerShell to do the job by analyzing external email sent to shared mailboxes. If a mailbox receives external email, then by definition the mailbox receives benefit from MDO, and that’s the test for requiring a license. https://office365itpros.com/2025/11/25/microsoft-defender-for-office-365-3/Microsoft Launches Preview of Exchange Admin API
Microsoft launched the preview of the Exchange Admin API on November 17. The new API is intended to close known feature gaps that exist in the Graph APIs and allow developers to migrate from EWS before Microsoft retires EWS in October 2026. Think of the Exchange Admin API as a discardable time-limited API that allows clients to submit cmdlets for processing. It’s certainly one way to approach the EWS problem! https://office365itpros.com/2025/11/18/exchange-admin-api-preview/
Outlook Encrypted Email Issues
I have deployed M365DLP controls to block password protected atachments that cannot be scanned and am telling users to use Outlook Encryption instead to protect outgoing email attachments. However, a number of external companies have reported not being able to open the encrypted messages and the screenshots provided show that they are trying to authenticate as a guest user in my Entra ID instance (rather than using their own IdP, SSO or an OTP). What would cause that and how do I resolve?
Title: Expose SHA-256 or SHA-1 for Mail Attachments in Microsoft Graph
Problem Email attachments in Graph don’t include a content hash. To identify or match attachments, developers have to download the entire file first. That wastes bandwidth and time and increases exposure. OneDrive/SharePoint already return hashes, but mail does not, so experiences are inconsistent. Request Add a server-provided content hash to every mail attachment. Prefer SHA-256. If that’s not feasible initially, expose SHA-1 as a minimum to align with existing Drive item hashes. Benefits Faster and cheaper: avoid downloading large files just to tell if you already have them. Deduplication: detect repeated attachments across threads and mailboxes. Security operations: correlate attachments with threat intel by hash and triage suspicious emails without fetching payloads. eDiscovery and compliance: confidently match the same document across mail and files. Consistency: a predictable, uniform approach across Mail and OneDrive/SharePoint.
