Office for Mac Issues

Fix Microsoft 365 Apps Not Opening on Mac After Purchase

Bushra Parveen Sep 29, 2026 869 views

Question details

The user is unable to launch Microsoft 365 applications on a Mac after purchasing a new subscription due to conflicting expired credentials.

How to Fix Microsoft 365 Apps Not Opening on Mac After a New Purchase

Product: Microsoft 365 for Mac
Device & OS: macOS
Scenario: Launching Microsoft 365 applications on a Mac after purchasing a new subscription to replace an expired one.
Observed behavior: Word, Excel, and other Microsoft 365 apps fail to open or activate because old login credentials remain stored in the macOS Keychain.

Before you start

Ensure you have the email address and password for your newly purchased Microsoft 365 account ready, and manually quit any frozen Office applications.

Solution 1Recommended

Clear Expired Microsoft Credentials from macOS Keychain

Removing old activation tokens forces Office to prompt for your new Microsoft 365 Premium account details upon launch.

This issue typically occurs when macOS continues to authenticate using a token from an expired subscription. Clearing these hidden credentials allows the system to register your new purchase without affecting any of your personal files.

Close all Office apps

Quit Word, Excel, PowerPoint, and Outlook completely. If they are unresponsive, use the Force Quit option from the Apple menu in the top-left corner of your screen.

Open Keychain Access

Press Command + Space to open Spotlight Search, type 'Keychain Access', and press Enter to launch the application.

Search for Microsoft entries

In the Keychain Access search bar at the top right, look for keywords associated with Office activation: 'Microsoft', 'Office', 'ADAL', 'Identity', and 'OneAuth'.

Delete outdated credentials

Select the old Microsoft Office or Microsoft Identity credentials from the list, right-click (or Control-click) them, and choose 'Delete'. Confirm the deletion if prompted by macOS.

Restart and sign in

Restart your Mac to apply the changes. Open Microsoft Word and sign in using only the Microsoft account that was used to purchase your new Microsoft 365 subscription.

Clear Expired Microsoft Credentials from macOS Keychain

No Data Loss: Removing credentials from Keychain Access only resets your Microsoft login state. It does not delete your documents, spreadsheets, or alter your new subscription status.

Solution 2

Verify Active Subscription and Reinstall Microsoft 365

If clearing the Keychain does not resolve the issue, verifying your account status and performing a clean reinstallation can fix corrupted app files.

Free Microsoft Office alternative

Try WPS Office for Mac When Microsoft 365 Fails to Open

If complex Keychain activation errors and subscription validations are disrupting your workflow, WPS Office offers a powerful, free, and lightweight alternative for Mac users. It installs instantly and lets you get straight to work.

1. Download WPS Office for Mac: Visit the official WPS website and download the free macOS installation package.
2. Install and Launch: Open the downloaded file, drag WPS Office to your Applications folder, and launch the suite.
3. Open Your Files Directly: Open your existing Microsoft Office files (.docx, .xlsx, .pptx) in WPS Office to continue editing immediately without any activation roadblocks.

Fully compatible with Microsoft Word, Excel, and PowerPoint formats (.docx, .xlsx, .pptx).Free to use with a lightweight installation that won't bog down your Mac.All-in-one suite design allows you to manage documents, spreadsheets, and PDFs in a single tabbed window.No complex Keychain activation errors or subscription lockouts to troubleshoot.

microsoft office alternative - wps office

Frequently Asked Questions

Will deleting Keychain credentials delete my Microsoft Word documents?

No, deleting credentials from the macOS Keychain only removes stored login tokens used for application activation. Your local documents, OneDrive cloud files, and active subscriptions remain completely safe and untouched.

Why does my Mac still recognize my expired Microsoft 365 subscription?

macOS stores authentication tokens securely in the Keychain so you do not have to log in every time you open an app. If an old token is not automatically overwritten by your new purchase, the Office apps will attempt to use the expired credentials and fail to open.

What if I cannot find 'ADAL' or 'OneAuth' in Keychain Access?

If you do not see those specific technical entries, simply search for 'Microsoft' and 'Office' in the Keychain Access search bar. Delete any application passwords, tokens, or identity preferences associated with Microsoft Office.

Can I use WPS Office to open my Microsoft 365 files on Mac?

Yes, WPS Office for Mac is highly compatible with all standard Microsoft formats. You can easily open, edit, and save documents in .docx, .xlsx, and .pptx formats for free, bypassing any Microsoft 365 activation issues.

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