Dependent tasks and milestones

[Terry Montgomery]

Greetings,
Ok, maybe I don't understand dependent tasks completely. Here's the deal. I
have a template project with tasks, start and finish dates, and durations
already set. I use this for a new project. I first set the Project Finish
date for the new project. No problem. Task #19 is "Receive Signed Contract".
It has no predecessor. It is a subtask of a Summary Task with a Start Date of
11/3/05.
I reset Task #19 as a Milestone with zero days. No problem. I then try and
reset the Start and Finish Date for the Milestone to 11/12/05. MS Project
refuses to let me reset the date. It maintains the Start and Finish Date the
same as the Summary Task Start Date of 11/3/05.
I try Task View and reset the date from there for the Milestone. It then
gives me an error message that the Milestone has a dependency on Task #117
which has a Start Date the same as the Summary Task of 11/3/05. Task #117 has
a predecessor of Task #14. I remove this predecessor from Task #117 even
though the Milestone is in a completely separate subtask group and has no
relationship to Task #14. MS Project still refuses to let me reset the
Milestone dates.
What gives?

Thanks,

Terry Montgomery

 

[Jan De Messemaeker]

Hi Terry,

First and before all: Project is not made for resetting start and finish
dates. It allows it (IMHO it shouldn't, those dates should not be accessible
for input) in certain circumstances but whenever there is a calculation rule
modifying it, it will happily forget the date you typed in.
That is like typing in the nett salary in a payroll package: when the tax
rules change the package will by all means recalculate the nett salary.

This being said, when I teach a course, I tell people that even after the
course, they can mail me any question on how Project works, and I'll always
do my best to answer, except on the one you just ask: "I'ma entering both
start and finish dates for a task, and don't understand what the package
does". That is because one shouldn't so I never went into the depth of the
logic behind this (sorry for the harsh word) wrong way of using the
software.

Now to try to understand your problem anyhow, first try to filter out all
statements on who is a summary task of who, because that does not influence
calculations.
Secondly forget about in which view you change things. That does not
influence the calculation either.

I think the origin of your problem lies in the statement "I first set the
finish date for the project" which introduces some funny calculation rules
(although it says that all tasks are planned as late as possible this isn't
true)

If you want to understand Project this is my advice:

- Schedule from Prioject Start date and not from finish date
- Do not touch start and finish fields, if you want to change dates always
go through Task information, Advanced and change the constraint of the task.
That way set Start or Finish and adjust duration.

HTH