My Bosch classix 1400 smells vile, its a rotting smell. I have tried several machine cleaners. Nothing seems to work.

I'm guessing that you use mainly biological detergents, and low temperature washes?

Just put the machine on its hottest wash, preferably 90 deg C. If you can get it to that temperature on a delicates cycle, then even better (water level is higher in delicates). A little chlorine-based cleaner, e.g. Milton or VWP, will help.

Once a bacterial biofilm has started growing, retail 'machine cleaners' can't properly penetrate it (and why would they ~ the makers want you to keep coming back for more). High temperature will always break down the biofilm.