Deep Dive into Microsoft Project Resource Pools: 5 Gotchas

sea-79606_1920In this article about resource pools, you’ll learn about a potential danger while swimming around in resource pools and hear about all the known gotchas I have run across in my dealings with resource pools.

An Important Note on Pool Safety and Security

Pool safety and security is important. After all, you’re sharing data with everybody who has access to the resource pool (via a linked project file). The concern that comes up the most is resource rates. Does John Doe need to know how much Jane Jill makes per hour? Will Jane get miffed when she finds out John is paid more for the same work? You betchya!

Unfortunately, Microsoft has never provided a solution for Microsoft Project Standard or Professional users. And since the cost of resources drives Project financial calculations, you really need to have something in that Rate column. Many of us resource “pool divers” have complained about this for years. (See this support blog post for an example of that.)

The easiest solution to this conundrum is to use blended rates for all resources when the rate is sensitive. In other words, don’t use the actual rate, but rather an average for a particular resource.

Say, for example that a support staff manager makes $200 per hour, and the lowest paid support staff makes $75 per hour. The blended rate for any instance of using a support staff resource is then $137.50, and that rate is used for all tasks assigned to any support staff entry in the resource pool. You might want to make a note of that in the resource pool itself, as this transparent strategy may appease any hate coming your way from HR.

If super precise calculations are needed (and blended rates won’t do), you’ll have to hire a smart VBA programmer to help you come up with a solution. (Feel free to contact me below, as I know a few of those.)

Part 1 of this deep dive teaches the theory and usefulness of Microsoft Project resource pools.

Resource Pool Gotchas

The following is a short list of potential confusions, frustrations and overall crazy things that I have encountered when using resource pools. Feel free to add to the list in the comment section below — I’m sure there are more!


When opening a resource pool in use, you’re presented with a cryptic dialog box with unfamiliar language. There’s no help for this box to speak of, so taking my recommendation (or one from others) is your best bet. The issue comes up because two or more people are not allowed to edit the pool at the same time (which would be crazy). So changes made to project resources when the resource pool is locked remain local to the project until both the project file and the resource pool are opened in read-write mode. Then the files are synced and the change is propagated.

A recommendation: On opening a resource pool in use, you will see this:


I always use the middle click if I need to have the pool open and when I’m doing any pool maintenance. Once created, most activity is coming in from the project files, so maintenance should rarely be needed once the pool is up and running. But if you need to change a name’s spelling or rate for all projects, use the middle path.

More Confusion

When opening a project file, you are again presented with a cryptic dialog box, asking you to open the pool (it will then present a read-only copy for your reference) or skip it.

All you must be aware of is that permanent changes aren’t made to the resource pool until both the project files and resource pool are opened at the same time, with the resource pool opened in read-write mode. See the first confusion above and follow the middle click.

A recommendation: When you see this screen, just click OK. Then you’ll see a copy of the resource pool with all the changes (pending or otherwise). If you prefer not to see this shadow copy of the resource pool, select Do not open other files.



If you see file paths instead of, say, a file name inside your resource pool, for example, with the Project field, don’t be alarmed:


A recommendation: That just means that the projects aren’t opened, which for some strange reason they must be. Here is what the pool looks like when the projects are open and all is good:


Broken Links and File Management Snafus

Just like using Master Plan and Subplans in Project, you need to pay attention to file locations to avoid broken links. Once a project file is linked to a resource pool file, moving or renaming the pool file will break the link and wreak havoc. Fortunately, you’re warned:

A recommendation: I advise a sensible file management strategy where a file/folder hierarchy is created and maintained and where resource pools are stored one level above folders that contain project folders. I also suggest never changing the name of the resource pool file.

In addition, never create a resource pool by copying another one (and then replacing the resources with new ones). Hidden gremlins may exist in a pool file created this way.

Currency Confusion

Projects linked to a resource pool should all be using the same currency. If you try to link a file whose currency differs from the pool’s base currency, you’ll be warned:


While Project allows you to have resources with different currency rates, costs calculations will go haywire and reporting will be a problem.

A recommendation: For projects using a resource pool, just make sure all files are working with the same currency.

This concludes our deep dive into resource pools. Have you figured out something about resource pools that is worth sharing? Make sure to include it in the comments below. Last one in is a rotten egg!

Part 1 of this deep dive teaches the theory and usefulness of Microsoft Project resource pools.
Part 2 offers a step-by-step tutorial with a real-life example.
Part 3 offers an important security consideration and shares the most common gotchas.

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Written by Jigs Gaton

Jigs Gaton is CEO of Phoenix Consulting and Training Worldwide, a company that helps developers design and implement better programs and build capacity with training and other resources. Jigs has over 30-plus years of experience in both the private and public sectors working as a project manager and PM consultant. He’s currently based in Kathmandu, helping organizations with post-earthquake reconstruction and other disaster-relief efforts.

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  1. I bit my tongue until this gotchas part of your series. The big warning for resource pools is that the link between resource pool and sharing files is the old windows technology Dynamic Data Exchange(DDE).
    DDE is not a stable technology (I don’t think its ever been updated). So if you ever rename, move or over-write any file you roll the file corruption dice. Pretty much every resource pool situation I have ever encountered has had file corruption issues sooner or later. Its when, not if.

    But wait, there’s more. If the files are stored on a disk drive that physically isn’t on your PC or in your immediate physical location, file corruption can also occur. Saving your files on a wide area network (WAN)? Don’t even consider a resource pool.
    With a resource pool you often also want a linked master file so you can see all projects. Now each file has two DDE links and twice the risk.

    So what other solutions are there? The one I implement is to create unlinked master files each week. Unlinked master files copy all task and resource data into a new file. Resource data is consolidated, so no need for a resource pool just for reporting. You also get a great audit trail over time (a new consolidated file each week).

    If you have more than a handful of projects, creating a new unlinked master file is arduous, so I use a VBA macro to do all the hard work. One click and the file creates itself.
    TIP: Interestingly time to create a new master is significantly less if I copy all files to my C: drive first.

    So because of file corruption issues I used my last resource pool more than 10 years ago and have always found alternative solutions ever since, though I have to confess my VBA skills make this much easier.

    Without VBA I suggest the most productive solution is to try Project Online and let Project Online provide its reliable resource pool and multi-project reports and more.

    Happy scheduling!

  2. @ Rod Gill: Interesting comment! I’ve personally never lost when “rolling the data corruption dice” on resource pools or master / subplans, but I have had problems with DDE linking throughout the Office ecosystem over the years… I think things are better in WIN 10, but that’s just a feeling I have (no facts available). Recovery options for broken links does exist in MS Project Pro, and that appears to work well, but the interface is a bit confusing to the end-user when first presented.

  3. 1) The pool and sharing project files should always be held in the same folder
    2) Should you take a copy of a file which is sharing resources with a pool you must always remember to break the link to the pool as soon as possible. Otherwise the pool will ‘see’ two files and double the resource load. Always double check and confirm the break by opening the resource pool after doing this to reassure yourself 🙂
    3) If combining files into a pool always make sure that the resources are called exactly the same thing and have the same information in all fields. If you have two Joe Doe entries but one has the initial “J” and one “JD” you’ll have two resources on your hands rather than a combined Joe Doe resource.

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    @ Miles: thx for contributing more “gotchas” !!! #2 is very important, and PMs need to know not to copy a .mpp file for use elsewhere, but always use the “New from existing project” feature instead. If you just copy the .mpp file you will have hidden “gotchas” galore…

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