Depending on the project settings, you will chose one of the following methods:
1) If the Project Settings are set so the PPM controls the WorkPlan, select Edit Workplan. Under the Actions menu, select Delete Work Plan.
2) If it is set to "Microsoft controls all shared work plan information" or "Control is shared", then you can temporarily change it to "PPM controls all shared work plan information", follow the steps above, then change it back to the original setting.
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