public { Public declarations } Windir: string; WindirP: PChar; Res: Cardinal; procedure TForm1.Button1Click(Sender: TObject); begin WinDirP := StrAlloc(MAX_PATH); Res := GetWindowsDirectory(WinDirP, MAX_PATH); if Res > 0 then WinDir := StrPas(WinDirP); Label1.Caption := WinDir; end;