I saw something similar once, although this may have nothing to do with your
problem.

The spreadsheet had a lot of underlines in various cells. The key is that
the underlines were "drawing objects" not formatting. That is, someone have
drawn lines under a bunch of cells rather than using an underlined font or a
border. This spreadsheet was intolerable just to scroll on.

Art

"KP" wrote:

One Excel file that our group uses responds EXTREMELY slowly when moving
around within the woksheet. It seems fine on a couple different computers and
is virtually intolerable on a couple others. Performance is consistent on
each machine (the slow ones are always slow, the normal ones are always OK).
Any ideas on what could possibly cause such a dramatic difference in this
one file?
Thanks.