Tip of the Day – PowerPoint 2007: Increase the Number of Undos You Can Do
Add More Levels of Undo
You can go back farther in Microsoft Office PowerPoint to undo actions.
1. With PowerPoint open, click the Office button, and then click PowerPoint Options.
2. On the Advanced tab, change the Maximum number of undos from the default 20 to any number from 3 to 150.