...
implementation
const
FOLDERID_Downloads : TGUID = '{374DE290-123F-4565-9164-39C4925E467B}';
function SHGetKnownFolderPath(const rfid: TGuid; dwFlags: DWORD;
hToken: THandle; out ppszPath: PWideChar): HResult;
stdcall; external 'Shell32.dll';
procedure TForm1.Button1Click(Sender: TObject);
var
DownloadPath: LPWSTR;
begin
if SUCCEEDED(SHGetKnownFolderPath(FOLDERID_Downloads, 0, 0, DownloadPath)) then
ShowMessage(DownLoadPath);
end;