2007 - Unable to Navigate past 2nd Worksheet
 

I've been running the Excel 2007 Beta for quite some time and this issue only
cropped up recently.

I can no longer view any worksheet past the first two in any workbook. When
I try, the program hangs and the zoom slider in the lower-right corner moves
back and forth between 82% & 83%.

The files I'm working on were creating in Excel 2007 and saved as Excel 2007
files. Now, the data on them seems to be inaccessible.

Any ideas?