SW will not automatically rebuild changes.

I have run into this issue all of a sudden on my new machine.  WIN7 with SW2009 SP4.0.  When I make a change to parts most of the time I need to manually do a rebuild to get the part to update.  This happens most of the time with configurations.  Did I forget to change a setting when I set up solidworks on this new machine.

Thanks

Todd

SolidworksParts And Features