The Svchost.exe file is located in the %SystemRoot%\System32 folder. At startup, Svchost.exe checks the services part of the registry to construct a list of services that it must load. Multiple instances of Svchost.exe can run at the same time. Each Svchost.exe session can contain a grouping of services. Therefore, separate services can run, depending on how and where Svchost.exe is started. This grouping of services allows for better control and easier debugging.
Svchost.exe groups are identified in the following registry key:
Each value under this key represents a separate Svchost group and appears as a separate instance when you are viewing active processes. Each value is a REG_MULTI_SZ value and contains the services that run under that Svchost group. Each Svchost group can contain one or more service names that are extracted from the following registry key, whose Parameters key contains a ServiceDLL value: To view the list of services that are running in Svchost: Tasklist displays a list of active processes. The /SVC switch shows the list of active services in each process. For more information about a process, type the following command, and then press ENTER: The following example of Tasklist output shows two instances of Svchost.exe that are running. The registry setting for the two groupings for this example are as follows: