Link-Layer Topology Discovery Mapper (lltdsvc) Service Defaults in Windows 7

Creates a Network Map, consisting of PC and device topology (connectivity) information, and metadata describing each PC and device. If this service is disabled, the Network Map will not function properly.

Default Settings

Startup type:Manual
Display name:Link-Layer Topology Discovery Mapper
Service name:lltdsvc
Service type:share
Error control:normal
Object:NT AUTHORITY\LocalService
Path:%SystemRoot%\System32\svchost.exe -k LocalService
File:%SystemRoot%\System32\lltdsvc.dll
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lltdsvc
Privileges:
  • SeImpersonatePrivilege
  • SeChangeNotifyPrivilege

Default Behavior

Link-Layer Topology Discovery Mapper is a Win32 service. In Windows 7 it won't be started if the user doesn't start it. When the Link-Layer Topology Discovery Mapper service is started, it is running as NT AUTHORITY\LocalService in a shared process of svchost.exe. Other system components, such as drivers and services, may run in the same process. If Link-Layer Topology Discovery Mapper fails to start, Windows 7 attempts to write the failure details into Event Log. Then Windows 7 startup should proceed and the user should be notified that the lltdsvc service is not running because of the error.

Dependencies

Link-Layer Topology Discovery Mapper is unable to start, if at least one of the following services is stopped or disabled:

Restore Default Startup Configuration for Link-Layer Topology Discovery Mapper

Before you begin doing this, make sure that all the services on which Link-Layer Topology Discovery Mapper depends are configured by default and function properly. See the list of dependencies above.

1. Run the Command Prompt as an administrator.

2. Copy the command below, paste it into the command window and press ENTER:

sc config lltdsvc start= demand

3. Close the command window and restart the computer.

The lltdsvc service is using the lltdsvc.dll file that is located in the %WinDir%\System32 folder. If the file is changed, damaged or deleted, you can restore its original version from Windows 7 installation media.