Hi Jill
Try this site:
Compatibility utility from
http://office.microsoft.com/en-us/pr...686761033.aspx
HTH
John


"Jill" wrote in message
...
I have a new lap top with Vista & the most recent version of excel & want
to
be able to open excel files I worked on from that lap top on my PC at work
using Windows XP & excel 2003. can I open an .xlsb file in excel 2003?
it
will not recognioze the .xlsb extension. what do I need to do to open it?