We've got an .xls that is used as a shared workbook. We're having a
problem where data that is saved to the worksheet is not visibly
propagating to other open instances of the worksheet. That is, if
someone enters a value in a cell and saves the worksheet, that value
is not displayed if someone else opens the worksheet, or updates the
worksheet if it's already open.

The odd thing is, if someone hits the refresh button on the web
toolbar, the updated data briefly appears in the worksheet as it's
loading, then disappears.

Any idea why this might be the case?

We're all using Exel 2003 on Windows XP Pro, SP2. The worksheet
resides in a shared directory on a file server. I've verified that all
parties concerned have proper access to the share.