When you enter a task, Microsoft Project gives each task a duration of 1 day by default. It would be an unlikely coincidence if, in fact, all your tasks really did last just 1 day. You’ll probably want to change the durations of most tasks.
You can assign durations to tasks using minutes, hours, days, or weeks. By entering just a duration for each task and letting Microsoft Project calculate the start and finish dates for you, you’ll create the most efficient schedule.
To change a task duration
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or press ENTER.