problems adjusting a duration

[Willie Kupersanin]

When assigning a duration to a task in Project 2003, I get an error ...

This action will cause a scheduling conflict. Task ### of xxxx has a
task constraint or is linked to a task that cannot move.

The task that is referred to in the error is a predecessor of the task
that I am working with. That task has a predecessor relationship with a
previous task.

Predecessor relationships are the only constraints that are set in the
project. No tasks have any completion percentages. No tasks have any
fixed dates (I verified this by filtering for tasks with fixed dates).
All tasks are set to start "As soon as possible" (verified by adding a
"constraint type" column).

Does anyone have any idea why I'm getting this error?
Thanks in advance!
--Willie

 

[Jan De Messemaeker]

Hi Willie,

There probably is a task with an Actual Start date.
If not do not hesitate to send me the file
You find my e-mail addrss on my website.

HTH

 

[Willie Kupersanin]

Thank you for your offer Jan!

I may have answered my own question. After posting to the newsgroup, I
went through the project and moved any predecessors from any summary
task to the summary task's individual sub-tasks. I'm not sure why I had
to do this, but it did make the scheduling error go away.
Thanks again!
--Willie