Rebuild improperly constructed schedule?

[Dave]

I have inherited a Proj2K mpp file that was constructed incorrectly
(Start/Finish entered manually for each of ~500 tasks, so all tasks
have constraints).

We have a requirement to make this into a "real schedule" with proper
task dependencies and ASAP constraints.

We need to maintain the start/finish dates that currently exist. I
have tried a number of approaches to modify the dates
programmatically, but because we are not scheduling forward from the
project start date (and in fact can't get agreement on exactly what
that date should be) I can't seem to remove the existing constraints
and get some of the dates to "stick".

I have tried several permutations and variations of:

Set Start1 = Start, Finish1 - Finish, Duration1 = Duration
Set Start = Start1, Duration = Duration1, and let Project calculate
Finish

but the existing data makes it impossible for Project to honor ASAP
for about half the tasks. Making these changes and then calculating
the project results in incorrect start/finish dates.

Can anybody suggest a way to approach this problem?

Thanks
Dave

 

[Steve House [MVP]]

The existing dates should NOT "stick" when you remove the constraints.
Having those dates there is why setting constraints is such a bad idea in
the first place and letting the dates change is the reason to remove the
constraints. What you can do, in order to preserve the original (but
fallacious) schedule, is before doing anything go to the Tools menu, choose
Tracking, choose Save Baseline, and on the baseline dialog box select the
Save Interim Plan radio button. This will take the current schedule's start
and finish for all the tasks into the selected interim plan "slot." Now
choose an arbitrary likely start date - you can always change it later - and
in the Gantt schedule, select all the tasks (click the little unlabled
button at the upper left corner of the Gantt table, at the top of the task
number column), click the Task Information button on the toolbar and on the
advanced tab change the constraint to ASAP. Your task dates will change to
reflect what they should have been all along had the plan been built
properly. Now you can see what the plan should have been / is now in the
main Gantt chart table and what your predecessor actually did by adding the
columns for the interim plan you used (start1/finish1, etc) to the tables to
compare the two.

You said you are getting "incorrect" dates. Undoubtedly you are getting
some DIFFERENT dates but I suggest to you that it is the original dates that
are the incorrect ones and the ones you're getting now are the CORRECT dates
you actually should have had all along had the plan been done properly from
the start. As I like to put it, Project is not to illustrate the dates you
want, rather it is supposed to predict the dates you're going to get with
the current plan, like them or not. If they don't meet your business
requirements, you have to change the plan - add/remove tasks, change task
sequences, re-deploy resources, etc - until they do.

 

[Dave]

Steve -
Thanks for your insight. I misspoke when I said making changes
resulted in "incorrect" dates - what I meant was basically what you
said, that the changes result in different dates. They are 'incorrect'
in the sense that they don't agree with the original start/finish
dates, but I digress.

I'm about to try your baselining suggestion, and I appreciate the tip.

Thanks
Dave