Microsoft 365 Message Center Categories Explained

Microsoft assigns a category to each Microsoft 365 Message Center item, which denotes the significance and potential impact of the update or change involved. This helps Microsoft 365 Product and Service Owners understand how urgently an item needs to be addressed and whether any action needs to be taken to resolve or prevent a pending service disruption.

In this blog, we outline what the different categories mean and give examples of M365 Message Center items which have been assigned these categories.

Prevent or Fix

Message Center items categorised as ‘Prevent or Fix’ inform those with access to the Admin Center of known issues which are currently affecting your organisation’s tenant. For these items, action may be required to avoid disruptions in service.

These messages are like a warning sign; they alert M365 Product and Service Owners of issues that need to be fixed or prevented before something occurs which would otherwise have a significant impact on the smooth running of your environment.

Example 'Prevent or Fix' M365 Message Center Item

MC799637 - Action Required: Check your Windows clients are up to date with security patches

This item, released in early June 2024, stated that Microsoft was implementing a security update to Entra ID, requiring all Windows clients to have security patches post-July 2021 to sign-in. Due to strengthened security measures, unpatched Windows clients would experience sign-in failures to Entra ID 

This item was categorised as high impact for both admin and user roles. If the required action is not taken, service disruption will occur, so it was categorised as ‘Prevent or Fix’.

These ‘Prevent or Fix’ Message Center items are different to Service Health (also accessible within the Microsoft 365 Admin Center), since they prompt proactive action to avoid issues which are likely to arise, as opposed to issues which have already occurred.

Service Health can be access within the Admin Center and shows tenant administrators the ‘health’ of services within their tenant. Here you can see known issues, so if you are experiencing an issue, you should check the service health to see if the issue you are having is known before calling support or trying to troubleshoot.

Plan for Change

Items categorised as ‘Plan for Change’ inform Product or Service Owners of changes to Microsoft 365 which may require action to avoid service disruptions. They inform Service Owners in advance of upcoming updates or changes which may require action, giving them warning.

Example 'Plan for Change' M365 Message Center Item

MC921105 – Product transitions to the cloud.microsoft domain – October 2024

This item had a high impact rating for both administrators and users and was categorised as ‘Plan for Change’ due to the need to ensure that *.cloud.microsoft domains are not blocked within organisations’ networks. This required developers to prepare in-house Teams apps to ensure that they functioned correctly under the new domain, as well as education of users to ensure they recognise cloud.microsoft as a key domain and to update any references to the old URL e.g., short links or bookmarks, to prevent confusion.

Stay Informed

M365 Message Center items categorised as ‘Stay Informed’ provide information to Product and Service Owners about new or updated features, which are being ‘turned on’ in your organisation. They do not require any action, but you should be aware of them.

Example 'Stay Informed' M365 Message Center Item

MC954674 – AI enabled file summaries on Teams mobile

This item was categorised as ‘stay informed’, meaning no action was required in relation to this item and at that moment in time, was not likely to cause any disruption. The rollout of this feature was said to be automatic, requiring no admin action, meaning it was assigned a low impact rating for administrators.

Knowing each M365 Message Center item's category should hopefully help Product and Service Owners focus their attention in the right areas, enabling them to know which of the hundreds of Message Center items are likely to impact their tenant and which require action to prevent service disruption.