Task dates and project end date changes when adding a percent complete or changing resources

Question

I have a large project plan using MS Project 2010. The only change I am making is changing the % Complete of a task to 100. It moves the finish date of the overall project and changes task dates for other tasks. It does not change the date of the task that I marked as 100%, as expected. When others make this change, the dates do not change. The same thing happens when I change a resource on a task. I am having difficulty determining what setting is causing this. How can I stop Project from changing the dates?

Some info on the project settings: All tasks types are Fixed work Entire project is at auto schedule No resource is set to 100%, everyone is either 70 or 50%

Answer 1

It is a bizarre quirk of MS-Project that setting a task to "Complete" by marking it as 100% Complete does not set the end-date to the current date. However I believe it does affect the task effort, since it reduces the outstanding amount to zero. If you had auto-levelling switched on, this could be allowing it to reschedule future work to take account of work planned for the future but now not required, and thus affecting the dates of other tasks in the project.

If your colleagues have auto-levelling switched off then no such re-scheduling will take place.

Answer 2

Assuming you are using Microsoft Project, take a look at your Calculation options in File > Options > Advanced. At the bottom of the Advanced page, there are options for how Project deals with the % complete and the status date. Those options will move tasks around based upon the status date and the % complete.

For example: you have a 5 day duration task that is scheduled to start on Monday and finish on Friday. Your status date is Tuesday evening. In the options you have selected the following:

• Move start of remaining parts before status date forward to the status date
• And move end of completed parts forward to the status date

According to the original plan you should be 40% complete (2 out of 5 days) by Tuesday evening. You enter 25% complete for the task. Project will move the start of the task to Monday afternoon so the 25% (1.25 days actual duration) aligns with Tuesday evening. The finish date will be extended to the following Monday so the remaining 75% (3.75 days remaining duration) begins after the status date.

See: https://support.office.microsoft.com/en-us/article/Set-the-status-date-41359205-4860-42e6-9b7b-2d702dcb52e3?CTT=1&CorrelationId=3b1355f6-4746-40a1-a689-c84594d08055&ui=en-US&rs=en-US&ad=US

for an in-depth discussion of how the status date and tracking changes schedules. If you don't want Project to reschedule the remaining duration leave all the options unchecked.