Fix Microsoft Excel for Mac Crashing with Code-Signing Error
Question details
The user needs to resolve an issue where Microsoft Excel for Mac closes unexpectedly upon launch, generating an error report related to the CODESIGNING subsystem.
- Product
- Microsoft Excel for Mac
- Device & OS
- Intel-based MacBook Pro running macOS 12.6.6
- Scenario
- Launching the Microsoft Excel application to view or edit spreadsheets.
- Observed behavior
- Microsoft Excel version 16.73 crashes immediately on startup. The Mac generates an error report containing EXC_CRASH, SIGKILL, and a code-signature failure.
Ensure you have your Microsoft account login credentials readily available, as you may need to reinstall the Office suite and reactivate your license to resolve corrupted application files.
Remove Recently Installed Excel Add-ins
Outdated or incompatible add-ins can interfere with application signatures and frequently cause code-signing failures during the startup process.
When Excel starts, it attempts to load all active add-ins. If an add-in is not properly signed for modern macOS security protocols or is corrupted, macOS will forcefully terminate the application with a SIGKILL command to protect the system.
Open Finder, click 'Go' in the top Apple menu bar, press and hold the 'Option' key on your keyboard, and click on 'Library' when it appears in the dropdown list.
Navigate through the folders to `Group Containers` > `UBF8T346G9.Office` > `User Content` > `Add-Ins`. This is where Microsoft Office stores custom extensions.
Drag any recently installed `.xlam` files or third-party add-in folders to the Trash. Once removed, attempt to launch Microsoft Excel again to see if the crash is resolved.
Uninstall and Reinstall Microsoft Excel
If removing add-ins does not fix the code-signing crash, the core Excel application files may be severely corrupted and require a complete reinstallation.
Switch to WPS Office for a Crash-Free Experience on Mac
If Microsoft Excel continues to crash or face code-signing errors on your Mac, consider switching to WPS Office. It provides a stable, lightweight, and highly compatible alternative that flawlessly handles your spreadsheets without the heavy resource drain or complex installation errors.
- 1. Download the Mac installer: Go to the official WPS Office website and download the free installation package tailored for macOS.
- 2. Install WPS Office: Open the downloaded file and drag the WPS Office icon into your Applications folder to complete the setup.
- 3. Open your existing spreadsheets: Launch WPS Office and directly open your .xlsx files. All your data and formatting will remain perfectly intact.
Frequently Asked Questions
What does a code-signing error mean on macOS?
A code-signing error (often showing as a CODESIGNING subsystem failure) means macOS has detected that the application's digital signature is invalid, corrupted, or has been modified. To protect your system from potentially malicious software, macOS forcefully closes the app, resulting in a SIGKILL crash report.
Can I manually fix macOS permissions to stop the Excel crash?
No. Manually repairing disk permissions is no longer supported on modern macOS versions (like macOS 12 Monterey). Permissions are maintained and repaired automatically by the system during regular software updates.
Will uninstalling Microsoft Excel delete my saved spreadsheets?
No, moving the Microsoft Excel application to the Trash only removes the program files. Your personal spreadsheet documents (.xlsx) saved in your Documents folder, Desktop, or cloud storage will remain completely intact.
