Use
You can simulate payroll for individual employees before performing the regular payroll run for all the employees in your enterprise. This is, for example, a good idea, if you have made complex changes to an employee’s master data, which may lead to far-reaching changes in his or her payroll results. In this way, you recognize sources of errors in time to make corrections before the regular payroll run. You can even simulate payroll for individual employees at any time during the regular payroll process, in order to trace the cause of any errors.

It is not necessary to simulate payroll for all employees before every regular payroll run. You can also make corrections at any time during the process of the
Scope of Function
A simulation run corresponds to a regular payroll run with the following restrictions:
Activities
You access the initial screen of the payroll program. The Test Run (No Update) indicator is set and cannot be changed.