Replacing Fonts Throughout a Presentation
If you're trying to change all the Times New Roman in a presentation to Garamond, you might be tempted to change the Title Master and Slide Master, and call it a day.
Unfortunately, if you've applied any manual formatting to individual slides, the "link" between the slide and its master might be broken. In that case, even if the master is updated, the slide might not make the switch.
To truly change all occurrences of Times New Roman to Garamond, choose Format, Replace Fonts. Choose Times New Roman from the Replace drop-down list; choose Garamond from the With list. Click OK to apply the change throughout the presentationeven in the masters. This solution is especially useful when you inherit a presentation created by someone who used a font you don't have.
Note
This technique changes only the font; you can't use the dialog box to change point size.