Hi Julie,
Thanx for your continued interest!Double click on Task ie task information.
Advanced -> calendar-> Assign "Short week"
Ceated new calendar. 25 hrs per week
Not sure if I creatred a task calendar - it is described a base calendar.
project 2010 - yes auto.

If you press F9, does the finish date change?

Hello Julie,
F9 did not help.
But I created a new Calendar (again) with the required working hours.
And it now works just fine.
I suspect that I had done something wrong when creating the calendar teh first time.
Thanks for your help.
Appreciated
;-)
And I will remember F9, which google tells me, forces recalculation!

You're welcome. It sounds like things may have been off in the other calendar. I'm glad you have it sorted and thanks for the feedback.

Julie