There are multiple projects open that share resources from the same pool
There are multiple project files open that share resources from the same resource pool. You may want to update the resource pool so that it has updated information from the sharers.
Using the Planning Wizard, you can:
Update the resource pool for only the active project.
Microsoft Project will update the resource information in the pool for only the active project. Other projects will not have their resource information updated in the pool.
Update the resource pool for all open projects using the same pool.
Project will update the resource information contained in the resource pool for all open projects (but not for those projects that are not currently open).
If you don't want the Planning Wizard to display this information again, select the Don't tell me about this again check box.