Stopping an R/3 System: Windows NT 
The following describes how to stop the R/3 System or individual instances using the SAP Service Manager. You can also perform these tasks using the Microsoft Management Console (MMC). SAP recommends the use of the MMC as it provides many new functions and simplifies system management. For more information, see
Microsoft Management Console: Windows NT.To stop an R/3 System that only consists of one central instance:
When the stoplights for all processes displayed in the SAP Service Manager window are "gray", the R/3 System has been stopped.

The SAP Service Manager checks the activity in an R/3 instance only when the processes of the instance have ended. Make sure that there are no active users or background jobs running before you shut down the instance. To do this, use the CCMS or the tools under menu options Tools
To stop an R/3 System that consists of several instances:
To access the CCMS stop functions, select Tools
® Administration ® Computing Center ® Management System ® Control ® System Monitor in the R/3 main menu.See: Starting and Stopping Instances
See also:
SAP Service Manager Start and Shutdown Processing under Windows NT