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Monthly Update #136 Available for Download
The Microsoft 365 for IT Pros eBook team is delighted to announce that the October 2026 update package is available for current subscribers to download. Refreshed EPUB and PDF files for all books are available from Gumroad.com using the link in the receipt issued on purchase. That link always fetches the latest book files. The following are now available:
| Book | Version | Production date |
| Microsoft 365 for IT Pros 2027 edition | #136 | 30 September 2026 |
| Microsoft Purview for IT Pros 2027 edition | #4 | 25 September 2026 |
| Power Platform for IT Pros | #4 | 30 September 2026 |
| Automating Microsoft 365 with PowerShell 2027 edition | #28.1 | 23 September 2026 |
Books have different production dates to reflect when they were generated during the monthly cycle. Details of changes can be found in our change log and help for downloading updates is in our FAQ.
Everyone knows about the volume of updates that occur inside a tenant every month. It’s also important to track the details of changes that Microsoft make to previously published notifications or roadmap items because it’s detail that drives the need for intervention. In addition to the small matter of announcing V3 of the Microsoft Graph PowerShell SDK and releasing V8.0 of the Microsoft Teams PowerShell module, here are just a few of the changes that happened over a selected three-day period in September 2026.
New Microsoft Graph Permissions for Groups
Our Microsoft Graph permissions check script turned up some important new granular permissions for Entra ID groups, including Group.ReadBasic.All and GroupMember.ReadBasic,All, low-permissioned permissions that are sufficient to handle tasks like checking that a group exists or creating a list of groups with minimal details, like display names and group identifiers. It’s no surprise to see this permission come along because Team.ReadBasic.All has existed for a while.
You should review any Microsoft Graph PowerShell scripts that use Group.Read.All to establish if such a high-level permission is warranted and downgrade where possible. The guidance remains to use GroupMember.Read.All for most group-related tasks, unless you really want to access group-associated resources, when you need Group.Read.All.
Extended Retirement Deadline for SMS Authentication, but Only for Some
As all Microsoft 365 tenant administrators should know by now, Entra ID is dropping SMS as a valid authentication method for multifactor authentication in a drive to make everyone use passkeys. The date for SMS retirement remains scheduled for 1 February 2027, except for global administrators and external users, both of which get an extension to 1 July 2027. Microsoft hasn’t revealed why the two groups get the extra four months to use SMS, and forcing global administrators to use passkeys would seem like an excellent idea, but that’s what is happening. B2B guest accounts can register passkeys for resource tenants with a feature update due to rollout in October (MC1459133, updated 14 Sept 2026).
Microsoft Plans to Fix Exchange Online Meeting Ownership Transfer Cmdlet
Following the release of the original Exchange Online Invoke-ChangeMeetingOrganizer cmdlet to transfer the ownership of meetings, we criticized Microsoft because of the lack of attention paid to Teams-enabled meetings, which could lead to data loss. In MC1472028 (14 Sept 2026), Microsoft says that they will address the issues in two phases following the initial rollout. The first will create new Teams meetings for transferred events. The second will transfer artifacts for transferred meetings to the new online event. Microsoft hasn’t committed to dates when this functionality will be delivered. In the interim, you can use our script.
It’s a 3 TB Limit for Exchange Online Auto-Expanding Archives
Microsoft announced that eligible accounts (anyone entitled to auto-expanding archives today) licensed for auto-expanding archives can grow archive mailboxes from the current 1.5 TB limit to 3.0 TB. The lack of precision about the newly increased limit and which accounts would benefit as published in the roadmap item was addressed in MC1472592 (15 Sept 2026). It’s a good example of why tenant administrators should wait for message center notifications before making firm plans for a new feature. Quite who’s going to use 3 TB of archive mailbox remains to be seen, but there will be some.
And Finally
We could go on and mention events like Microsoft retirement of Azure Email Communication Services and the introduction of a Pay-as-you-go plan for OneDrive for Business storage (at the same time as Microsoft cancels the old 25 TB expansion option), but we won’t. Instead, we close out this month by noting that our Planner plan which synchronizes with the Microsoft 365 admin center hit the 9,000-task limit for a plan. Fortunately, we had a PowerShell script ready to clean up the plan by removing 1,596 completed tasks that were more than five years old. I have no idea why Microsoft chose 9,000 as a good maximum for tasks in a plan, or 3,000 for the limit for active tasks in a plan. In any case, you know now.
We hope that you enjoy the October update.