Actual Start Date in MS Project

Question

I have a problem: I have a schedule that is baselined, constructed using horizontal and vertical logic, constraint free, fixed duration. I have a work package / task that has a FS dependency. The predecessor is not finished; however, the dependency is soft and we were able to start the successor. I want to enter the actual start date but, when I do, schedule removes the start date and replaces it with NA. It will also not allow me to update the percent complete.

The weird thing is, I have a duplicate task in another control account, same dependency, same duration, same set up, and it did allow me to enter an actual date.

What could be the cause of this?

Update: I need help asap. Hypotheses are welcomed!!

Answer 1

Moved from "Comments" secton -

I have no idea of the cause but when I get a MSProject task acting "wonky" I create a new, identical task and then delete the misbehaving one. Copy/paste doesn't seem to work, I have to create the new task manually.

Answer 2

Sometimes this happens when you copy the entire row and the only resolution is to create a new task. When you copy the row, MS Project copies over a lot more than what meets the eye. For instance, it copies the task, the resources and the assignment.

If you want to copy tasks safely, you should copy it one column at a time. This will only take the data and not everything behind the scenes.