Office 365 Desktop License Activation Loop on macOS – Error "Your account doesn't allow editing on a Mac"

Hello everyone,

I am opening this thread because I am stuck in a persistent licensing/activation loop with Microsoft 365 desktop applications (specifically Excel and Word) on my macOS device, and I am running out of options.

The Problem: Every time I launch Excel or Word on my Mac and complete the authentication process using my corporate/organization account, the application forces a read-only state and displays this persistent banner: "Your account doesn't allow editing on a Mac. To learn more, contact your admin about your Office plan."

This is completely blocking my workflow because I absolutely need to use Power Query, which is heavily limited or unavailable in Excel for the Web. I must get the desktop app running.

Crucial Context:

• The account works flawlessly on a Windows PC. On Windows, I can edit files, run Power Query, and the desktop license is fully recognized. This confirms that the Microsoft 365 subscription tier definitely includes desktop application rights and is fully active. The issue is strictly confined to macOS.
• My IT administrator checked the tenant backend and insists everything looks perfectly green and active on their end.

Exhaustive Troubleshooting Already Performed (Client-Side): To avoid repetitive basic advice, please note that I have already executed a complete purge of the Office environment on this Mac, following the standard documentation:

1. Official License Removal: I ran the Microsoft Office License Removal Tool (Microsoft_Office_License_Removal.pkg) to completely wipe local licensing files.
2. Keychain Access Purge: I opened Keychain Access and deleted every single credential, token, and certificate matching Microsoft, Office, ADAL, or Identity under both the Login and System keychains.
3. Deep Cache & Container Deletion: I navigated to ~/Library/ and forcefully deleted the following directories:
   • ~/Library/Group Containers/UBF8T346G9.ms
     • ~/Library/Group Containers/UBF8T346G9.Office
       • ~/Library/Group Containers/UBF8T346G9.OfficeOsfWebHost
         • ~/Library/Containers/com.microsoft.Excel
           • ~/Library/Containers/com.microsoft.Word
             • ~/Library/Preferences/com.microsoft.Excel.plist
             1. Background Process Isolation: I completely shut down and disabled background synchronization services (like OneDrive Sync Service) via Activity Monitor to make sure no background processes were locking configuration files during re-authentication.
             2. Fresh Reinstallation: Completely uninstalled the entire Office suite and performed a clean reinstall.

Despite entirely resetting the local identity metadata, as soon as I type my email and log back into Excel, the app immediately falls back into the exact same "read-only/no-editing" loop.

Since the client-side system environment has been entirely cleared, this seems to be a server-side token mismatch or a tenant-level synchronization bug specifically targeting macOS endpoints.

Has anyone encountered this specific cross-platform behavior where Windows works but Mac is rejected? Are there any hidden backend tenant settings, Entra ID propagation delays, or Conditional Access policies that might trigger this specific error on macOS without showing anomalies on the main M365 Admin Center?

Any help or advanced technical guidance would be greatly appreciated.

Thank you!