Hyperlink creation problem
 

I've searched the group and not found a problem like mine. I have a
column of hyperlinks. When the workbook is first opened the links
display as plain text and are not active. If you select the cell and
hit F2 to rdit the cell and then hit <ENTER the cell becomes active
and works mormally. If you save the changes the next time you open the
workbook you get a 404 error when you select the hyperlink until you
do the F2 <ENTER thing then it works normally again as long as the
the workbook is open.

What could cause this? How can it be corrected? Please help!