Determine if Service Already Installed

Determine if a Windows service is already installed.

Note:This software is available as a pre-release.

Download the Chilkat Service ActiveX here: ChilkatService.zip
Unzip and register with regsvr32.

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls,
    OleCtrls;

...

procedure TForm1.Button1Click(Sender: TObject);
var
service: ERROR;
retval: Integer;

begin
service := TChilkatService.Create(Self);

service.ServiceName := 'MyService';

//  returns -1 for failure (inability to check)
//  returns 1 if already installed.
//  returns 0 if not yet installed.

retval := service.IsInstalled();
if (retval < 0) then
  begin
    ShowMessage('Failed to query service control manager');
  end
else
  begin
    if (retval = 1) then
      begin
        ShowMessage('Service is already installed');
      end
    else
      begin
        ShowMessage('Service is not installed');
      end;
  end;
end;