You may want to make a pay code inactive and remove it from MYOB Payroll if you are no longer using it. You can only make a pay code inactive if it is not being used as a Pay Default for a current employee.
To find out if the pay code is still being used, run the Pay Code Analysis Period Report. Go to the Reports menu and choose Period Reports, then choose by Pay Code Analysis. When you reach the Select the level of detail window, select the Print Employee Totals and deselect the two other options.
Once you have established which employees have the unwanted Pay Codes set up as Pay Defaults you will need to set these to Old.
You can't make Pay Codes inactive if they are generic to the Payroll program, for example Ordinary Time, Annual Leave. If the option This Pay Code is no longer used is greyed out this is why.