A family of Microsoft word processing software products for creating web, email, and print documents.
Do not overwrite the 300-page document; first duplicate it, then determine whether the equations are still present but not rendering, and restore an earlier version only if the equation objects are actually missing.
1. Protect the recoverable document
- Quit Word.
- In Finder, duplicate the document and give the copy a new name.
- Perform all testing on the duplicate.
- Avoid Recover Text for now. That operation is intended to extract text from damaged files and can discard formatting or non-text objects such as equations.
A selectable box where an equation was located can indicate that the embedded object remains, although it does not establish which equation system created it.
2. Test one equation object
Open the duplicate and test only one blank equation:
- Double-click it or select it and press Return/Enter.
- If the equation opens in an editor, its content still exists and this is primarily a display/rendering problem.
- If Word offers to convert the equation, accept the option to convert all equations in the file to Office Math Markup Language (OMML), but only in the duplicate. Microsoft documents this conversion for equations created with the retired Microsoft Equation Editor; minor font or spacing changes can occur, and long division is not supported by the converter.^1^
If no conversion prompt appears, do not repeatedly edit or save the original. The equation may already use OMML, may come from another equation product, or may no longer contain recoverable content.
Microsoft previously fixed a Word for Mac equation-editor defect in version 16.96.2, but that issue concerned opening the editor and converting typed expressions—not equations becoming blank after the current update.^2^
3. Restore a version from before the update
If the document is stored in OneDrive or SharePoint:
- Open the file in Word.
- Select the document name in the title bar.
- Select Browse Version History.
- Open a version dated before the Office update.
- Confirm that several equations display correctly.
- Save that version under a new filename, or select Restore if it is the required copy.
Version History applies to files stored in OneDrive or SharePoint.^3^
If the document is local, restore a pre-update copy from Time Machine or another backup rather than replacing the current file.
If Word closed unexpectedly and changes were not saved, check:
- Finder → Go → Go to Folder.
- Enter:
/Users/<username>/Library/Containers/com.Microsoft/Data/Library/Preferences/AutoRecovery
- Copy any matching AutoRecovery file elsewhere before opening it.
Word deletes an AutoRecovery copy when a document is closed with Don’t Save, so this is only a fallback for an unexpected shutdown or unsaved session.^4^
4. Conditional fixes based on the equation type
If the equations were created with MathType: open one blank object in MathType. A closely matching report describes MathType equations becoming empty boxes after an Office update while remaining editable in MathType. Report the problem through Word → Help → Feedback → Report a Problem, and check with Wiris/MathType for a compatible update.^5^
If symbols appear after editing but remain blank in normal view: check the equation font. Word uses Cambria Math as its default equation font.^6^
- Open macOS Font Book.
- Search for Cambria Math or the font used by the equation editor.
- If duplicate versions exist, resolve the duplicates and retain the newest active copy.
- Restart Word and reopen the duplicate document.
Microsoft documents duplicate, missing, and substituted fonts as causes of Office for Mac rendering problems.^7^
5. Escalate with diagnostic details
If the equations remain blank in both the current file and a known-good earlier copy:
- In Word, record Word → About Microsoft Word version and build.
- State whether the equations are Word/OMML, old Equation Editor, or MathType objects.
- Attach a small sanitized sample containing one affected equation.
- Submit it through Help → Feedback → Report a Problem and contact Microsoft Support.
Microsoft’s current Word for Mac issues page includes equation and rendering investigations, but it does not document this exact Tahoe 26.5.1 blank-equation symptom as a confirmed issue.^8^
References
- Newer versions
- Equation Editor may not open or convert expressions as expected in Word for Mac | Microsoft Support
- Microsoft 365
- macOS
- MathType rendering in Word - Microsoft Q&A
- Linear format equations using UnicodeMath and LaTeX in Word | Microsoft Support
- Issues with fonts in Office for macOS | Microsoft Support
- Fixes or workarounds for recent issues in Word for Mac | Microsoft Support