Changing the dates on an already set milestone

[sarah]

My question
I am trying to update a project plan that has already been created.
The milestones and task dates have already been identified.
I am able to change the date for the tasks themselves, but not for the
milestones.
Why is this?
I am just selecting the drop down on the date that is already populated and
selecting the new date...but nothing happens
Also, when I double click on the Milestone start or end date I get a
dialogue box. The tab with in that box that allows you to input the date is
grayed out. Is this a restriction that has been set up by the creator
themselves?

 

[sarah]

My question
I am trying to update a project plan that has already been created.
The milestones and task dates have already been identified.
I am able to change the date for the tasks themselves, but not for the
milestones.
Why is this?
I am just selecting the drop down on the date that is already populated and
selecting the new date...but nothing happens
Also, when I double click on the Milestone start or end date I get a
dialogue box. The tab with in that box that allows you to input the date is
grayed out. Is this a restriction that has been set up by the creator
themselves?

 

[Steve House]

Sarah, Got bad news for you. You're not really changing task dates either.
Projects function is to CALCULATE schedules, not merely document schedules
arrived at through some other means. You don't tell it task and milestone
dates, it tells you. When you use the little drop down calendars or
manually type dates into the Start and Finish fields, you are actually
setting a Start No Earlier Than or a Finish No Earlier Than contraints, NOT
really the same thing as setting a start or end date at all. Tasks and
milestones are driven into the positions in the schedule by a combination of
factors - primarily being their links from their predecessor tasks, the
durations of those predecessor tasks, and the availability of the resources
with the skills to do the work. Remember I mentioned a moment ago the SNET
constraint? If you select a date from the little drop down in Start, you
are designating the EARLIEST date it is permitted to start. But links and
resources may very easily dictate that it really can't start that early
after all and so will have to be scheduled later. I'll bet what you're
trying to do is move it up to be sooner than it's showing and it's not
cooperating. Without seeing your file I can't be absolutely certain but 999
times out of a 1000 what you're experiencing is due to what I've described.