You can edit tasks depending on their status and your security rights. For example, you can edit a task description, custom attributes, or end date.
For an Open task in a Task List, you cannot edit the start date, because the task has started. You can only change the duration or the end date. You also cannot edit instructions, questions, Assignee, or approver, and you cannot add, delete, or edit predecessors. You can reassign the Assignee or approver from the Task Actions workflow.
Select the Attributes tab.
Custom Attributes are created in: Defining Custom Attributes.
>To add an attribute, select Actions, and then Add. Enter:
Select an attribute from the list of defined attributes.
This noneditable field is populated by the Attribute.
Select a value associated with the type of attribute; for example: a numeric value for Formatted Number attribute, a List for List attribute, multiple lines of displayed text without scrolling for Multi-Line Text, a name of a person, User, or Yes or No for the Yes/No attribute.