I have been inserting equations into my powerpoint 2010.

I realized that after I have created the equation and save/closed the presentation.

I discovered that when open the presentation again, the text box containing the equation have been converted to drawing.

This is very frustrating as I can no longer edit the equations or copy the created equations for other slides that need to be created.

Appreciate any help given to retain the equations so that it is editable after saving.

Thanks and Best Regards,
Sunny