A different equation opens in MathType than the one double-clicked in Word

The information on this page applies to:
MathType for Windows and Mac• All supported versions of Word for Windows and Mac

After opening a previously saved Word file containing MathType equations, you double-click an equation to edit it. The equation that appears in MathType is different than the one you double-clicked in Word.

The equation you double-clicked is not the one that opened in MathType.

In any Microsoft Word document with MathType equations, there are two sets of data that synchronize to make up the equation objects. Those two types of data are WMF data, which stands for Windows metafile, and MTEF, or MathType equation format data. Windows looks at the WMF data and MathType looks at the MTEF data. Both types of data are synchronized under normal circumstances, but the data in the files you're working with has become unsynchronized, or broken.

This is how the break in data occurs…

When users copy equation objects from one Microsoft Word document to another, or even copy and paste an equation object within a Word document, this can cause the problem. Microsoft Word will try its best to interpret both sets of data, but sometimes fails to do so. It has trouble interpreting the MTEF data, and breaks the equation object. It is best practice when copying an equation out of Word, to open MathType via 'Insert Inline Equation' (or other command), then paste the equation into MathType and close MathType. As a result, MathType will insert the equation into the Word document. The two sets of data in Word are synchronized when inserted this way, and tend to remain synchronized.

The best way to perform copy/paste operations and ensure these problems don't happen is to follow these steps when you want to re-use an equation in a document:

  • Copy the desired equation from the Word document.
  • Use the 'Insert Inline' (or just 'Inline') equation button in Word to launch MathType where you need to paste the equation.
  • Paste the equation into MathType and close MathType.
  • The equation will now be in the document at the desired location.

Note that generally this is caused by copying a MathType equation from one place in a document and pasting it into another place in the document, or into a different document, then perhaps double-clicking to edit it. Therefore, following the process above is the best way to prevent this problem (copy the equation and paste it into MathType — do not paste it directly into Word).

With respect to repairing or recovering the affected equations, unfortunately we have not found a way to do so. You must re-type the equations in order to correct them. This is an issue we continue to investigate, but so far we know of no way to prevent this from happening, nor to recover the equations, except by following the steps above.


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.