You can change the owner of an automated report in Task Centre and remove users who are no longer active. Follow these steps to change task ownership:
Log in to TaskCentre and open the Tasks folder.
Double-click the task to open it.
Click the General tab.
Locate the Owner dropdown.
Click the Owner dropdown and select the new owner.
Click OK.
Repeat steps 2 - 6 for all relevant tasks.
Once you've updated all relevant reports, remove the user following these steps:
Click System, then click Users.
Right-click the user and select Delete.