OneDrive Error Codes

Fix OneDrive and Teams Sign-In Errors 1200 and 8004dec5 on macOS Sonoma

Amos Gikunda Oct 14, 2026 869 views

Question details

Users are experiencing persistent sign-in loops and specific error codes when attempting to log into Microsoft OneDrive and Teams on Mac computers running macOS Sonoma.

How to Fix OneDrive and Teams Sign-In Errors on macOS Sonoma

Product: OneDrive and Microsoft Teams
Device & OS: macOS Sonoma (macOS 14)
Scenario: Logging into OneDrive or the new Teams application after upgrading the Mac operating system and completing multifactor authentication.
Observed behavior: The applications repeatedly display the sign-in window and return error codes such as 1200 or 8004dec5 instead of granting access to the user's account.

Before you start

Ensure you have administrative access to your Mac and save any open work, as you may need to restart your computer or applications during the troubleshooting process.

Solution 1Recommended

Use the Microsoft Office License Removal Tool

Clearing corrupted or outdated license files is the most effective way to break the authentication loop and resolve sign-in errors on Mac.

This is a known issue involving macOS 14 (Sonoma) and Microsoft's authentication tokens. Running the official license removal tool clears out cached credentials that are causing the continuous sign-in prompts.

Download the Tool

Navigate to the official Microsoft Support website and download the Office license removal tool for Mac.

Run the Installer

Open the downloaded .pkg file from your Mac's Downloads folder and follow the on-screen prompts to install and run the removal script.

Restart and Sign In

Once the tool finishes, restart your Mac. Launch OneDrive or Teams and enter your Microsoft 365 credentials to generate a fresh authentication token.

Use the Microsoft Office License Removal Tool

Data Safety: Running the license removal tool will not delete your personal files, synced OneDrive data, or Teams chat history. It only removes hidden activation files.

Solution 2

Create a Microsoft 365 Support Ticket

If local troubleshooting fails, escalating the issue to Microsoft Support is necessary to investigate your specific environment.

Free Microsoft Office alternative

Try WPS Office for a Seamless Mac Productivity Experience

If persistent authentication bugs and sign-in errors in Microsoft Office apps are disrupting your workflow on macOS Sonoma, consider switching to WPS Office. It provides a lightweight, highly compatible, and frustration-free environment without complex licensing loops.

1. Download for Mac: Visit the official WPS website and download the macOS installer.
2. Install and Launch: Drag the WPS Office icon to your Applications folder and open the app.
3. Open Your Files: Directly open your existing .docx, .xlsx, and .pptx files without needing complex licensing or Microsoft sign-ins.

Fully compatible with Microsoft Word, Excel, and PowerPoint formats.Avoids Microsoft 365 authentication loops and sign-in errors on macOS Sonoma.Lightweight architecture ensures smooth and fast performance on Mac.Free to download and use with an intuitive, familiar interface.

microsoft office alternative - wps office

Frequently Asked Questions

What causes error 1200 or 8004dec5 in OneDrive on macOS Sonoma?

These errors are generally caused by a known compatibility issue between macOS 14 (Sonoma) and Microsoft's authentication token system, which results in a continuous loop during multifactor authentication.

Will removing my Office license files delete my local documents?

No, the Microsoft Office license removal tool only clears activation data and cached credentials. Your personal files, folders, and documents remain completely untouched.

How can I prevent this sign-in loop from happening again?

Keep both your macOS Sonoma operating system and your Microsoft Office applications fully updated. Microsoft and Apple frequently release patches that address backend authentication bugs.

Can I use WPS Office if my Microsoft 365 account is locked out?

Yes. WPS Office operates independently of Microsoft 365 licensing. You can open, edit, and save your existing Microsoft Office files locally using WPS Office without needing to sign into a Microsoft account.

Microsoft Office Error Codes