Illegal start date bug?

[Andrew]

Is the following issue a Microsoft Project bug? The issue goes as follows:

I encountered a project file which has 2 tasks, let's just call them T1 and
T2. These tasks are not summary tasks and they are not milestone tasks.
There is a start-to-finish link from T1 to T2. Both tasks have ASAP
constraints. Each task has several resources assigned to it, and all
resources are using the Standard calendar.

Now here's what seems like a problem to me: T1's Finish Date is Mon 2/7/05
at 5:00pm, and T2's Start Date is Mon 2/7/05 at 5:00pm... the same exact
time that T1 ends. It seems like a problem to me because whenever I try to
duplicate these circumstances in a new project file, Project will
automatically update T2's start date to Tue 2/8/05 at 8:00am, which makes
sense because of the Standard calendar. It doesn't make sense to start T2
at 5:00pm because of the Standard calendar... no work would get done.

Is this a bug? If not, how can I reproduce such a project file from
scratch?

Regards,
Andrew

PS - I am using Project 2003.

 

[JackD]

It is possible that calculation has been turned off or perhaps there is some
slight rounding error so that TI is really finishing a tiny bit before 5.
Another alternative is to check to see if there is a task calendar for T2
which is different from standard. I'd guess that reproducing this situation
would be difficult. It isn't really anything to worry about I think.

 

[Gérard Ducouret]

Hello Andrew, hello Jack,
Another possibility : the T2 task duration is in "elapsed" days : "ed"

Gérard

 

[Andrew]

Sorry, but none of these selections are what I'm looking for.

1. Calculation is not turned off. It is set to automatic.
2. I don't think it is a rounding error, because when I change the start
date for T2 manually, I can set it to a multitude of strange times. I can
set the start to Mon 2/7/05 6:00pm, 7:00pm, 8:00pm, and Project doesn't mind
any of those start dates!
3. Actually, both T1 and T2 are using calendar "None", so they are
completely following the resource calendars, which are all Standard.
4. And the T1 and T2 durations are in normal days, not elapsed days.

Any other possibilities?

 

[Steve House [MVP]]

When you change the start time of a task manually you are not really
changing the start time at all, if that makes any sense. Manually entering
a value in the [Start] field sets a Start No Earlier Than constraint. So if
my calendar says work takes place between 8am and 5pm and I enter "22 Mar 05
06:00" as the start time in the Start column of the Gantt chart, the task
will be scheduled to start at 8am. Why? We've said it can't start any
*earlier* than 6am but there's no one there at that hour to do the work so
Project delays it until someone comes in at 8am. If you look at the task
information and check the constraint info, you'll see it does in fact say
6am.

When you assign resources, the resource calendar takes over control of the
task from the Project calendar. Does your T2 have a resource assigned and
if so, does the resource calendar show he goes home later than 5pm? It's
not enough to see that they all have their calendars *based* on the standard
calendar. View the resource sheet, double click the assigned resource's ID
number and review the hours shown on his personal copy of the calendar for
the date in question. Even though is calendar might be *based* on the
standard calendar, his copy can and often will be edit to show different
hours of work. For example while the standard calendar might show
0800-1700, his personal version has been edited to show 0830-1730 and that
would account for the behavior of T2 you're observing. IF there's more than
one resource assigned, check all of their calendars as Project schedules
resources independently of each other and if even one resource out of the
group can work later than 5pm, the task will start at 5.