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On upgrading to v12 any existing pay code groups that were created under Payroll > Maintenance > Pay Code Group will be accessible under Rates and Rules > Maintenance > Pay Code Group and will have been assigned a pay code group type of Payroll. Any existing pay code groups that were created under Rates and Rules > Maintenance > Pay Code group will continue to be accessible in the same area and will have been assigned a pay code group type of Rates & Rules.
When creating a new pay code group, it is now mandatory to select the pay code group type that identifies whether the pay code group is for use in Rates and Rules or the Payroll module. An example of this is shown below.
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For more information, see Pay Code Group Maintenance.