Background Information
When you use cut and paste to move published tasks in your Microsoft Project plan, duplicate tasks appear in the user's timesheet, and one of the two tasks has a large black X indicator in the Indicators column. When you perform a cut and paste action on a task, you are actually deleting the original task and creating a new identically named task. Because of this, you should move the task by dragging and dropping it rather than using Cut and Paste for this purpose.
Resolution
To manually move a task, perform the following steps:
1. Break task dependencies between this task and other tasks
2. Select the row header (gray block to the left of the task name), then drag and drop the task in its new location
3. Reset task dependencies as needed
4. Indent or outdent tasks as needed
5. Click Collaborate - Publish - All Information
Note: If you actually need to delete a task, you should always close out the task first. Set all Remaining Work value to 0 hours for all resources assigned to the task and then click Collaborate - Publish - New and Changed Assignments. After doing so, delete the task and then click Collaborate - Publish - All Information.