as screenshot, why my father task (Create DS<Batch: file->file>) has 52hrs work when sum of 2 child task is just 12h? any idea are appreciated! ![enter image description here][1] update: I'm using Microsoft project 2010 solved: **So, check to make sure that none of your summary tasks have resources assigned** [1]: https://i.sstatic.net/SqtGF.jpg