Simulating Operation Mode Switching 
Use
Before you switch an operation mode in the system, you can simulate this switch.
Procedure
To start the simulation from the R/3 main menu, choose Tools
® CCMS, Control/Monitoring ® Control panel, Control ® Switch OP mode ® Simulation.The test log describes the possible switches and the errors that may occur, which you can then avoid for the "real" operation mode switch.
Also see:
Switching Operation Modes