Paul said:
Is there any way to prevent additional time reporting on a task that
has one resource and is 100% complete?
If you are using Project Server 2003 you could use managed time periods
to close the time period in which the task falls and prevent this.
But the larger question is: if someone is still working on it, is it
really 100% complete?

As much as this sounds like the tree in the
woods philisophical question it holds some real truth here. How is it
possible that the resoruce still thinks there is work to be done? Was
the task defined in a way that made it possible for there to be an
opinion about it's completeness?
Remember that while there is a way to prevent, in some cases, users
from reporting time the bigger problem is that time reporting happens
AFTER they did the work. If there is a task definition or assignment
problem that allows this to happen then you are loosing time because by
the time they get to the timesheet to report the hours they have
already expended effort. I would address this issue before worrying
about the timesheet locking thing. But that is just me.
