I’m getting the following error message: Task number X already exists in this project. The next available number is Y. Why?

You will see this error when you try to save your information for a newly created task when a sequence such as the following occurs:

1. You click on the “Add a Task” button and AceProject displays the Edit Task Information page. You will notice that AceProject automatically populates the Number field with value X.
2. While you are still viewing the Edit Task Information page, another user in your account clicks on “Add a Task” to add a task in the same project. Because you have not yet saved your changes, AceProject automatically populates the number field with the same task number (X).
3. This other user clicks on “Save” and records the data for task X in your account database.
4. When you click on “Save” to record your new task, AceProject detects that the project already contains a task with task number X  in the database. Since AceProject knows you are trying to add a new task, it will not allow you to overwrite the data for existing task  X. Instead, AceProject will allow you to change your value in the Number field and it will inform you of the next available integer task number (number Y).