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MS Project 2007 Duration is not calculating correctly RRS feed

  • Question

  • In MS Project File, I have put in 12 days duration for a task is starting 1/23/14 and should end on on 2/10/14.  But instead, the date is pushing out to 2/18/14.  There are no holidays on my calendar and it is a basic five day/40 hour work week.  I reduced the duration to test that tasks and when I added 5 days of duration, the task went from 1/23/14 to 2/3/14.  I've checked to make sure the Auto Calcuation Function is selected, Project is set on "Fixed Duration, but the box is not checked, and I've even duplicated the tasks with the same results.  And there are no other links driving this tasks besides the predecessor that got me to the 1/23/14 date. What am I missing?
    Monday, December 16, 2013 5:30 PM

Answers

  • Hi,

    I'm prety sure you have the classical mismatch between your working time and the definition of "a day". How many working hours are there in a d(real) day? I suspect 7 (let's assume that. Now your duration is "12d" but Project doesn't really use d as a time unit, only the minute. So you have to define whet is a day. From your statement about a week, I suspect it is stiull set to 8 hrs.

    So when you enter 12d, Project in the background translates that to 96 hours. It will then calculate when to "spend'" 96 working hours according to your (say) 7 hrs per (real) day working time and come up with (96/7=)almost 14 real working days, and that is what you see.

    Before entering any data in a Projct, make sure the definition of a day (in the calendar options) is identical to the number of working hours in the calendar (found in Change Working Time).

    Greetings,

    Monday, December 16, 2013 6:01 PM
    Moderator

All replies

  • Hi da_raw1,

    It can be caused by many reasons. Do you have any resources assigned to the task? Then check the resource calendar. Isn't the task splitted? Can you create the same task in another project file and check it out?

    When I do as you did, actually the 12d task should end on february 7th.

    You could check in the resource usage view to check how the work is spread?

    Hope this helps.


    Guillaume Rouyre - MBA, MCP, MCTS

    Monday, December 16, 2013 5:50 PM
    Moderator
  • Have you checked task constraint in task information window.

    http://office.microsoft.com/en-in/project-help/change-the-task-type-project-uses-to-calculate-task-duration-HP010092039.aspx

    http://support.microsoft.com/kb/175457/en-us

    Also check in Task information --> Advanced --> Calendar whether you have assigned correct calendar. 


    kirtesh

    Monday, December 16, 2013 5:55 PM
  • Hi,

    I'm prety sure you have the classical mismatch between your working time and the definition of "a day". How many working hours are there in a d(real) day? I suspect 7 (let's assume that. Now your duration is "12d" but Project doesn't really use d as a time unit, only the minute. So you have to define whet is a day. From your statement about a week, I suspect it is stiull set to 8 hrs.

    So when you enter 12d, Project in the background translates that to 96 hours. It will then calculate when to "spend'" 96 working hours according to your (say) 7 hrs per (real) day working time and come up with (96/7=)almost 14 real working days, and that is what you see.

    Before entering any data in a Projct, make sure the definition of a day (in the calendar options) is identical to the number of working hours in the calendar (found in Change Working Time).

    Greetings,

    Monday, December 16, 2013 6:01 PM
    Moderator
  • No resources are assigned to the task, but here's something odd.  I took the same exact tasks, put them in a completely blank schedule and I still got the same results; 1/23/14 to 2/18/14.  There are no constraints and the calendar is set for "Standard" which is M-F, 8 to 5.  What the heck am I missing?
    Monday, December 16, 2013 6:15 PM
  • Hi,

    Jan mentionned a very good point. You must check that your working time ("tool" menu, modify working time, then click on the "work weeks" tab and "details") is the same than the calendar options in options/calendar tab. Meaning that both should have the same working time, ie 7 or 8hrs a day.

    Hope this helps.


    Guillaume Rouyre - MBA, MCP, MCTS

    Monday, December 16, 2013 6:19 PM
    Moderator
  • Perfect!  That did the trick. I checked the working time and it was set at 12hr days and 72hrs a week.  Once I made it 8/40, it was correct with the durations.  Thanks for your help on this. 
    Monday, December 16, 2013 7:49 PM
  • You're more than welcome!

    Guillaume Rouyre - MBA, MCP, MCTS

    Monday, December 16, 2013 7:54 PM
    Moderator
  • Hi,

    Jan mentionned a very good point. You must check that your working time ("tool" menu, modify working time, then click on the "work weeks" tab and "details") is the same than the calendar options in options/calendar tab. Meaning that both should have the same working time, ie 7 or 8hrs a day.

    Hope this helps.


    Guillaume Rouyre - MBA, MCP, MCTS

    I have the issue the other way, where my task duration is 5wks, but the start finish dates work out to be 24 days, i am using a 7 day working week, when i change to 35 days the work out correct.  Please help.
    Monday, November 4, 2019 4:34 PM
  • Tails123,

    Rather than tacking on to a very old thread, why not create a new post. In that post tell us which version of Project you are using, how your 7 day calendar is set up, whether your tasks are manually scheduled or auto-scheduled, whether you have separate task and/or resource calendars, what is your definition for a "day". And if you can, a screen shot would help.

    John

    Monday, November 4, 2019 7:03 PM