The actual factory tool used by BMW engineers. It is far more powerful than Carsoft and, while the interface is more technical, there are countless "one-click" installers available on forums like Bimmerfest or Bimmerforums.
A laptop with a native DB9 serial port is highly recommended for stable data transmission. Modern Alternatives to Carsoft bmw carsoft 65 sp1 crackszip free
If you are looking for "free" or low-cost diagnostics for your older BMW, the community has largely moved on to more robust, stable options that are also free to download: The actual factory tool used by BMW engineers