When you add delay time to a task, you delay not only that task but also its successors. If you add a delay to a critical task, for instance, you can cause the project finish date to occur later. Allowing Microsoft Project to automatically resolve resource overallocations can add delay time to both critical and noncritical tasks that have overallocated resources, with sometimes unpredictable results. If you have just a few overallocated resources, you might get better results if you add delay to tasks yourself.
When you add delay to a task manually, you can check the effect on the resource’s allocation, and then adjust the delay further if needed. So that you don’t affect the finish date of your schedule, first delay tasks that won’t delay the project finish date (those with total slack). Add delay time only up to the amount of slack time for each task. It’s useful also to delay noncritical tasks before tasks on the critical path.
Experiment with adding delay times to different tasks to see the effect on your schedule. Note that delay time is always given in elapsed time and that nonworking time is included in the delay time.
To delay a task with an overallocated resource
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