Critical path - sometimes wrong

[Erkki Piipari]

Hi.

Sometimes MSP shows the critical path and sometimes it
does not (no critical tasks except a few constrained
ones). Is this behavior somehow dependent on the system
(current case test environment). Somehow the system sets
the Crtical field to No.

Options :
- calculate multiple critical shows all critical

I have not changed the task bar style or other settings.

PS I checked MS knowledge base and newsgroups - no hits.

Responses would be of great value.
Thank's in advance !

Erkki

 

[Steve House]

That can happen with constraints - try creating a project file starting
tomorrow with 4 1-day tasks A, B, C, D, and a Finish milestone, linked in a
line FS. Set the finish date of the milestone manually to 01 Dec (sets a
Finish No Earlier Than constraint) or set a Must Finish On constraint of 01
Dec. Format the Gantt chart to show the critical path and you'll there
isn't one. Why? The tasks take the next 4 work days to finish, ending the
middle of next week, and then there's a long gap until we get to the
milestone on Dec 01. Thus those tasks have a positive float, they could be
delayed some period of time, without delaying the project finish milestone,
and thus they aren't critical tasks. Why the gap? Because we've instructed
Project to place that milestone on the 1 dec or at least no earlier than 1
Dec and it's obeying our instructions. IMHO, constraints are way overused
by many people. They have their place but should be used with extreme
caution and understanding of their full effect.