Missing vertical lines
 

I have MSO Excel 2007 SP2. When I open the a new page, I can see my
horizontal lines, but not my vertical lines. When I highlight the entire
page, I can see them. If I highlight several columns, I can see them. I can
see them if I add borders. I tried uninstalling and re-installing, I just
upgraded to SP2, but got the same result.

Any suggestions?