As you mentioned the doc files are old, and the issue happens after the Microsoft update, please see the information below: If the equations were created by Equation editor 3.0, they can’t be viewed or edited in Office 2016 for Mac, because the Equation Editor 3.0 is no longer supported by Office 2016. However, these objects can still be edited if you have the MathType plugin installed. Microsoft Word 2010 For Mac free download - Microsoft Word, Microsoft Office PowerPoint 2010, Microsoft Office Publisher 2010, and many more programs.

TechNote 74

Applicability

The information on this page applies to:
  • MathType for Windows and Mac
  • Equation Editor (e.g., Microsoft Equation 3) for Windows and Mac
All supported versions of Word for Windows and Mac
Microsoft Equation 3.0 For Mac

Issue

Many users become concerned when their equations are replaced with empty boxes or appear in gray-shaded boxes. Double-clicking these boxes will launch MathType and display the equation, and the equations will print correctly, but the equations are not displayed properly in Microsoft Word.

Reason

Microsoft

The 'empty boxes' behavior is a feature in Microsoft Word called 'Picture (or Image) Placeholders' designed to conserve RAM. The Picture Placeholders option helps minimize the amount of computer resources required to display a page and helps Word scroll multiple pages faster on-screen. So long as your computer does not have insufficient RAM, you can toggle this setting so the equations in your document display on-screen.

The 'gray-shading' behavior is a setting called 'Field Shading' designed to make finding equations and other OLE objects easier when they can be difficult to see among surrounding content.

Equation

Solution

Mac

Microsoft Equation 3.0 For Mac High Sierra

As these are features of Word, it is advisable to refer to Word's Help files to learn more about them and how they are activated.

If none of the equations or other graphics in your document display (Windows only)

If you find that all of the graphics in your document are not being displayed, Picture (or Image) Placeholders is probably enabled. To turn this option off, do the following:

Download
  1. Select
    • Office button | Word Options | Advanced |Show document content (Word 2007)
    • File tab | Options | Advanced | Show document content (Word 2010 and later)
  2. Uncheck the box for Image Placeholders or Picture Placeholders.

If this was the cause, unchecking this option will cause all the objects in the document to be displayed again.

If some or all of the equations or other graphics in your document display in a gray-shaded box

If you find that some or all of the graphics in your document display in gray (or striped) boxes, Field Shading is probably enabled. To turn this option off, do the following:

  1. Select
    • File tab | Options | Advanced | Show document content (Word 2010 and later)
  2. Under Field Shading, select Never from the pull-down menu.

If this was the cause, setting this option to Never will cause all the objects in the document to be displayed properly again.


We hope this has been helpful. As always, please let us know if you have questions about this, or if you have additional techniques that work. We'd love to hear from you.

Microsoft Equation Editor 3.0 is no longer distributed with Microsoft Office.

To continue editing and working with equations in Microsoft Office, get MathType now!

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Microsoft Equation 3.1

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Microsoft Equation 3.0 Windows 10

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