Office for Mac Issues

How to Fix Word Startup Errors Caused by EndNote on macOS Sonoma

Maira Mehtab Oct 1, 2026 868 views

Question details

Users are experiencing issues where Microsoft Word fails to launch or crashes after updating to a new OS version due to an add-in conflict.

Fix Word Startup Errors Caused by EndNote on macOS Sonoma

Product: Microsoft Word, EndNote
Device & OS: macOS Sonoma (14.4.1)
Scenario: Attempting to launch Microsoft Word after upgrading the Mac operating system.
Observed behavior: Microsoft Word fails to start or crashes immediately upon launch because the EndNote Cite While You Write add-in is incompatible with the operating system.

Before you start

Before making changes, verify your current versions of macOS, Microsoft Word, and EndNote to ensure you are downloading the correct patches for your specific setup.

Solution 1Recommended

Update EndNote and Microsoft 365

Installing the latest updates for both applications can resolve known compatibility bugs introduced by macOS Sonoma.

Software developers frequently release patches to address OS upgrades. Ensuring both Microsoft Word and EndNote are fully updated is the most effective way to restore functionality.

Update Microsoft Word

Open Microsoft Word (if it launches in Safe Mode) or another Office app like Excel. Click 'Help' in the top Apple menu bar, and select 'Check for Updates' to open Microsoft AutoUpdate.

Update EndNote

Launch the EndNote application on your Mac. Click 'EndNote' in the top menu bar, and choose 'Check for Updates'.

Restart Your Mac

After applying all available updates for both programs, restart your Mac and attempt to open Microsoft Word normally.

Solution 2

Remove and Reinstall the Cite While You Write Add-in

If updates do not fix the issue, manually removing the EndNote add-in from Word's startup folder can clear corrupted integration files and stop the crashes.

Solution 3

Reinstall Applications and Contact Support

As a last resort, performing a clean installation of the software or seeking direct developer assistance may be necessary for persistent compatibility issues.

Free Microsoft Office alternative

Switch to WPS Office for a Stable Mac Experience

Tired of troubleshooting Microsoft Word startup errors and add-in incompatibilities? WPS Office offers a lightweight, highly stable environment for macOS, allowing you to edit your documents seamlessly without the bloat.

1. Download the Mac Installer: Visit the official WPS website and download the macOS version of WPS Office.
2. Install WPS Office: Open the downloaded installer and drag the WPS Office icon into your Applications folder.
3. Open Your Documents: Launch WPS Office, click 'Open', and select your existing .docx files to instantly resume your work.

Fully compatible with Microsoft Office formats, including .docx, .xlsx, and .pptxLightweight architecture that runs smoothly and quickly on macOS SonomaFree to use with an intuitive, all-in-one tabbed user interfaceFewer startup conflicts and crashes compared to heavy Microsoft Word setups

microsoft office alternative - wps office

Frequently Asked Questions

Why does the EndNote add-in cause Word to crash on macOS Sonoma?

macOS Sonoma introduced new system frameworks and security updates. If the EndNote Cite While You Write (CWYW) add-in is not fully updated to support these architectural changes, it creates a conflict during Microsoft Word's startup process, resulting in a crash.

Where is the Microsoft Word Startup folder located on a Mac?

You can access the Word Startup folder by opening Finder, holding the Option key, and clicking Go > Library. From there, navigate to Group Containers > UBF8T346G9.Office > User Content > Startup > Word.

How do I open Microsoft Word in Safe Mode on a Mac to bypass add-ins?

Unlike the Windows version, Word for Mac doesn't have a direct Safe Mode shortcut for the app itself. However, you can start your Mac in Safe Mode by restarting it and holding the Shift key until the login window appears. This clears system caches and helps identify if an add-in is causing the issue.

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