Making changes in the timephased portion of the view causes a conflict with another task
The timephased edit will cause one task to finish after the start of another task to which it is linked. Because tasks in this project are required to honor their constraint dates, the only way to keep the timephased edit on the task is to remove one or more of its task links.
Using the Planning Wizard, you can:
Keep the timephased edit and remove the link.
Microsoft Project will keep the changes you made to the timephased portion of the view and remove the link between the tasks. To keep Project from overriding the constraints you place on tasks when there is a scheduling conflict, click the File tab, click Options, then in the Schedule tab select the Tasks will always honor their constraint dates check box.
Ignore the timephased edit.
Project will remove the timephased edit you made and will not change the links or constraints that are applied to the tasks.
If you don't want the Planning Wizard to display this information again, select the Don't tell me about this againcheck box.