In this post I will continue with work and cost type of resources and problems when assigning them to the task.

As I mentioned in my previous blog, there are three types of resources:

1. Work resource. This type of resource
   includes people and equipment needed to complete the task in a project
2. Cost resource. This type of resource includes financial cost which does not depend on the duration of task, for example airplane ticket
3. Material resource. This type of resource, also called consumable, is the resource you need to complete the task in a project, for example bricks, concrete etc.

First I will define resources needed for my task.

John the Trainer is Work resource and his standard rate is $100 per hour.
Airplane ticket is Cost resource and it does not have the defined price yet.

Now I will define task called Training

In the first example I will assign only cost resource to the task.

I assign Airplane ticket to the task and I told the MS project that it costs $1000.

I will now assign John the Trainer to the task.

And I got:

Duration, Start and Finish date are the same, so everything seems O.K

Here is another example. Suppose that I assigned only cost resource (Airplane ticket) to the Task (as it is shown in 3^rd picture above). Now I will mark the task as 100% completed.

Everything looks fine! But, suppose that you forgot to assign John the Trainer to the task AFTER you marked the task 100% completed. I will assign John now:

Now look what happens:

Duration is now 0 days (milestone???) with unchanged Start and End date?
It seems like a bug. And you will get the same thing if you assign both resources (Airplane
ticket and John the Trainer) to the task and then, after you mark the task as
100% completed, you remove John the Trainer.

What will happen if you do not have cost resource (airplane ticket) assigned with
the task, and you assign Work resource (John the Trainer) with the task AFTER you
mark the task 100% completed? I will assign John now:

and I will get:

So, obviously the problem is with the cost resource type (in our example the Airplane ticket).

What is the solution? If you have to add or remove work resource to the task after it is completed (25%, 50%, 75%, or 100%) first mark the task as 0% completed, then add or remove the resource to the task and after that mark task as completed again.

I will show to you what happens if I add Work resource (John the Trainer) with the task AFTER I marked it as 50% completed and I already have work resource assigned to the Task. I will assign John now:

and I will get:

Duration is only 50% of expected (1,5 day instead of 3 days) and this is bug.

So, once again, first mark the task as 0% completed, and then add or remove the resource to the task and after that mark task as completed again.

See you,