When you send your tasks to Microsoft Project (MSP) read/write from Clarity, the tasks 100% completed appear in the MSP Gantt not as completed bars but as not-worked time (a dotted line).
The dotted lines indicate time frame in the task where no work is entered. This can be reflected in parts of the task or the entire task is 0 work assigned to the task
Below is an example of a scenario where this can happen by design by using both Actual Work and Remaining work:
2. From the Gantt view, you can see where dotted lines show up where there are gaps where there is no remaining work or actual work:
3. This can also happen if there are 0 hours of work on the task. In this case, the entire task will show as a dotted line in the Gantt. The one option to workaround this is to remove all the assignments from the task if they are not going to complete any work for the task.
If you right-click within the Gantt chart and select Bar Styles, you can customize how the dotted line appears:
For more information on split tasks in working with the Microsoft Project integration, see: MSP: Task Integration with Classic PPM