This command enables or disables Emergency Management Services for the specified operating system boot entry. bcdedit /ems ...

This command enables or disables Emergency Management Services for the specified operating system boot entry.  bcdedit /ems [] { ON | OFF }          Specifies the identifier of the entry to be modified.  Only             "Windows boot loader" entries can be specified. If not specified,             {current} is used. For more information about identifiers, run             "bcdedit /? ID".  Example:  The following command enables Emergency Management Services for the current operating system boot entry:      bcdedit /ems ON