I work in Excel 2003. I have a large file with about 3000 lines. It links
to another file that is about the same size (7800KB). I often move them into
new directories or change the file name. I change the source on the target
file using edit links change source. It takes 2 hours to update (I have a
relatively new laptop with 1000mb memory and a 715 processor).

I notice that the update button is always on automatic, and the manual is
grey, so I am not able to change from automatic update to manual. My
computer gets locked up for this time. I would like to change the links more
quickly. Is my problem this automatic update? Why can't I change it to
manual? Would changing to manual solve my time problem?