uses
 WinSvc;
function ServiceGetStatus(sMachine, sService: PChar): DWORD;
 {******************************************}
 {*** Parameters: ***}
 {*** sService: specifies the name of the service to open
 {*** sMachine: specifies the name of the target computer
 {*** ***}
 {*** Return Values: ***}
 {*** -1 = Error opening service ***}
 {*** 1 = SERVICE_STOPPED ***}
 {*** 2 = SERVICE_START_PENDING ***}
 {*** 3 = SERVICE_STOP_PENDING ***}
 {*** 4 = SERVICE_RUNNING ***}
 {*** 5 = SERVICE_CONTINUE_PENDING ***}
 {*** 6 = SERVICE_PAUSE_PENDING ***}
 {*** 7 = SERVICE_PAUSED ***}
 {******************************************}
var
 SCManHandle, SvcHandle: SC_Handle;
 SS: TServiceStatus;
 dwStat: DWORD;
begin
 dwStat := 0;
 // Open service manager handle.
 SCManHandle := OpenSCManager(sMachine, nil, SC_MANAGER_CONNECT);
 if (SCManHandle > 0) then
 begin
  SvcHandle := OpenService(SCManHandle, sService, SERVICE_QUERY_STATUS);
  // if Service installed
  if (SvcHandle > 0) then
  begin
  // SS structure holds the service status (TServiceStatus);
  if (QueryServiceStatus(SvcHandle, SS)) then
  dwStat := ss.dwCurrentState;
  CloseServiceHandle(SvcHandle);
  end;
  CloseServiceHandle(SCManHandle);
 end;
 Result := dwStat;
end;
function ServiceRunning(sMachine, sService: PChar): Boolean;
begin
 Result := SERVICE_RUNNING = ServiceGetStatus(sMachine, sService);
end;
// Check if Eventlog Service is running
procedure TForm1.Button1Click(Sender: TObject);
begin
 if ServiceRunning(nil, 'Eventlog') then
  ShowMessage('Eventlog Service Running')
 else
  ShowMessage('Eventlog Service not Running')
end;
{
 Windows 2000 and earlier: All processes are granted the SC_MANAGER_CONNECT,
 SC_MANAGER_ENUMERATE_SERVICE, and SC_MANAGER_QUERY_LOCK_STATUS access rights.
 Windows XP: Only authenticated users are granted the SC_MANAGER_CONNECT,
 SC_MANAGER_ENUMERATE_SERVICE,
 and SC_MANAGER_QUERY_LOCK_STATUS access rights.
}
{
 Do not use the service display name (as displayed in the services
 control panel applet.) You must use the real service name, as
 referenced in the registry under
 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services
}