If there is one reason to upgrade to PowerPoint 2010 (2007 also solves this), this is it.
But here you are, the corporate IT department insists on keeping the company on Office 2003, and you just got your 45-page back from your boss who "edited things for clarity" and you're on to present tomorrow morning 9:00.
This will save you:
- Right click the chart
- Go to the bottom: "format object"
- Now resize the chart back to 100% by 100%
- Close the object
- Open it as you would do normally (you are 0.01% of the population) and resize properly.