Workbooks

Hi all,

I have a following situation:

I work on 3 computers and on all of it I have Exel 2007. I create workbooks and save them. But on first computer a workbook is saved with extension *.xls, on second - *.xlsm, and on third - *.xlsx. Why does it so? What and where I have to set up for saving my workbooks with one extension?

Regards,

Veronika.