A task can be setup to be enabled during certain dates and by day of the week.First you can enable or disable a task by a date range. If the entry date is between the start and end date then the task will be enabled for the user. Start and end dates are optional so if you leave them blank there is no start or end date. The second way to enable or disable a task day is by the day of the week. On the bottom of the task editor is the seven days of the week. If you wish to only allow a user to enter time on Monday thru Friday, then check Monday thru Friday and uncheck Saturday and Sunday. The timesheet will then only have the Monday thru Friday time enabled.