My Tassimo machine (Bosc 40) has a light that comes on every so often. It is a red/orange light. This comes on to tell you the machine needs to be descaled, or cleaned. To clean it, you can either use plain h2O or use a descaling disk that fits into the coffee capsule where you put your coffee T-Disc. Then you fill the water reservoir with water, and press the start button. I think you hold this button for a few seconds longer than whne making coffee/ latte/ other regi\ular drinks. the machine should then operate and go through about four times the amount of water for a songle cup of java. After it cycles completely through all the way through alll the water, refill the reservoir and the coffee outht to taste/ look/ smell better. Mine always has, anyway. To get better and or more complete instructions, check the website for your machine type (mine is Bosch) and or through wherever you get the coffee from. Good luck, snd G’d bless. ple410