This error message usually appears because the last time payroll was run for the employee's pay group, the Final Run checkbox was enabled when generating salaries and allowances.
There are two ways to resolve this:
The payroll user will need to go back to the generate salaries and allowances screen, clear the Final Run indicator check box and re-run generate salaries.
If timesheets were confirmed, then reversing the timesheets is required. This will bring payroll back to before the Pay290 is generated. CorePay, Input, Reverse Timesheet Confirm.