uses Registry; 
 
procedure TForm1.Button1Click(Sender: TObject); 
var 
  reg: TRegistry; 
  b : bool; 
begin 
  CopyFile('C:\DOWNLOAD\FP000100.TTF', 'C:\WINDOWS\FONTS\FP000100.TTF', b); 
  reg := TRegistry.Create; 
  reg.RootKey := HKEY_LOCAL_MACHINE; 
  reg.LazyWrite := false; 
  reg.OpenKey('Software\Microsoft\Windows\CurrentVersion\Fonts', False); 
  reg.WriteString('TESTMICR (TrueType)','FP000100.TTF'); 
  reg.CloseKey; 
  reg.free; 
 {Add the font resource} 
  AddFontResource('c:\windows\fonts\FP000100.TTF'); 
  SendMessage(HWND_BROADCAST, WM_FONTCHANGE, 0, 0); 
 {Remove the resource lock} 
  RemoveFontResource('c:\windows\fonts\FP000100.TTF'); 
  SendMessage(HWND_BROADCAST, WM_FONTCHANGE, 0, 0); 
end;