Tasks have uneccessary slack time & don't update.

[Mark Osterbrink]

I have a situation with four tasks, Task A (release drawings), Task B (build
tools), Task C (build assembly equipment), and Task D (build parts). Tasks B
and C can't start until Task A is complete. Task D can't start until Tasks B
and C are completed. In the original timeline, everything was linked
Finish-to-Start. Task B takes longer than Task C, and in order to prevent
being "late" with task C, I made it "As Late As Possible". This worked fine,
and Task B and C completed at the same time.
An opportunity came up to reduce the duration of Task B, but when I change
the duration of it, the other tasks don't update correctly. Task C maintains
its previous start and finish dates, with a big slack between the finish of
both Task A and Task B.

Any idea why, or how I can fix it?

 

[JulieS]

Hi Mark,

I quickly tried your scenario and was unable to reproduce the problem but
here are a couple of suggestions to check:

1) Is the Calculation Mode (Tools>Options Calculation tab) set to manual?
2) Does Task C have an Actual Start Date?

Hope this helps. Let us know how you geta long.

Julie

 

[Mark Osterbrink]

Thanks for the response.

I tried it the way I described it, and it works fine, so it most be
something specific to my timeline. Tasks B and C are composed of many
smaller tasks which are gathered under a summary task, and portions of task C
can't be completed until task B is completed.

Calculation is automatic, and nothing changes if I press the "Calculate"
button.

Aha! I found it. Some of the tasks have a percent complete greater than
0%. If I set it to 0%, they move as I anticipated.

 

[JulieS]

Hi Mark,

Glad you found the answer. When tasks have a % complete other than 0, they
have an actual start date. Until the actual start date is removed (by
re-setting the % complete to 0), the tasks won't move.

Thanks for the feedback.

Julie