When attempting to assign a team member to a task, the Resource list is empty (or missing some team members) even though there are resources on the project team.
Expected Results: Both team members show up as available to assign to the task.
Actual Results: Only the resource with 100% Allocation shows up. The resource with 0% allocation does not show up.
This is due to the default filter value being set to 'No' for 'Zero Allocation'. Any resources with zero allocation to the project (defined on the project team tab) will not show up as available to assign to the task.
Click 'Show All' which will reset the 'Zero Allocation' value to 'All'. The resource with 0% allocation will then show up.
As a permanent fix if you would like to be able to assign resources with zero allocation to a task:
If the above doesn't help, see also: No or a few resources show up when you try to assign a user to a task