Microsoft 365 for Mac: Editing Issue

To All Users

Information Collaboration Center (ICC)

■ Overview

Microsoft has announced that, as of July 13, 2026, the certificate used for license authentication in Microsoft 365 apps for Mac will be updated. Due to this change, users running older versions of macOS or Microsoft 365 apps may become unable to edit documents in Word, Excel, or PowerPoint. If you are using macOS, please review the information below and update your system and applications as needed.

Reference:

◇ Microsoft Official Announcement (Minimum Requirements for macOS / iOS)

https://learn.microsoft.com/en-us/microsoft-365-apps/mac/certificate-update-mac-ios

■ Required Versions (as of July 2026)

To use Microsoft 365 apps without issues, both macOS and the Microsoft 365 apps must meet certain minimum version requirements.

[macOS Version / Microsoft 365 App Version]

If your macOS or Microsoft 365 apps are older than the versions listed above, you may become unable to edit documents in Microsoft 365 apps. Please make sure that both your macOS and Microsoft 365 apps meet the required versions.

■ Steps to Check and Resolve the Issue
　　Please follow the steps below in order.

1. Check your macOS version

Open the Apple menu → About This Mac. If your macOS version is earlier than macOS 14, please update to the latest version.

Reference:

◇ Check which macOS version is installed

https://support.apple.com/en-us/109033

◇ How to download and install macOS

https://support.apple.com/en-us/102662

2. Check the version of your Microsoft 365 apps (Word / Excel / PowerPoint)

Open each app and check the version from About Word, About Excel, etc. Version 16.83 or later is required. (If you are using version 16.83 or later but still cannot edit documents with your university account, please contact ICC.)

Reference:

◇ About Office: How to check which version of Office you are using

※ Switch the tab to Mac

https://support.microsoft.com/en-us/office/lifecycle/lc-account/about-office-what-version-of-office-am-i-using

3. Update your Microsoft 365 apps

Open any Microsoft 365 app → Menu bar → Help → Check for Updates

You can update to the latest version from there.

Reference:

◇ Update Microsoft 365 or Office on macOS or iOS devices

https://support.microsoft.com/en-us/office/lifecycle/officeinstall/update-m365-office-macos-ios

◇ How to manually update apps from the App Store

https://support.apple.com/en-us/102629

4. If "Check for Updates" does not appear in the Help menu

Sign in to the following page using your university Microsoft 365 account. Then select Install Apps to download the installer and reinstall (update) Microsoft 365 apps.

https://m365.cloud.microsoft/apps

Instructions for signing in with your Microsoft 365 account and installing Microsoft 365 apps are available under the Microsoft 365 section on IISS.

5. After updating Microsoft 365 apps

Open Word, Excel, or other Microsoft 365 apps and sign in with your university Microsoft 365 account.