Because Windows Media Player 12 is built into the OS, "downloading" it usually means enabling or repairing the existing installation. Windows Media Player Legacy - Microsoft Support

Windows Media Player 12 is the latest version available for Windows 7. Unlike typical software downloads, it is as a core component of the Windows 7 operating system. You do not need to download it from a third-party website; instead, you can manage or reinstall it directly through your system settings. How to Get the Latest Version on Windows 7