Water sitting in well (where the coffee goes) - doesn't drain

I had a problem on my Tassimo T65 where water was entering the bottom drip tray through the small hole at the rear. It seems many people have this problem but after researching on line there is little help although I found on this sit how to take the coffee maker apart and from that thread the possible cause for my own issue.
So if your machine seems to be leaking from the small drain hole to the rear of the drip tray try this before you think it is either in need of specialist repair by Bosch at a cost almost the same as a new machine or before you start to take it apart and have a look yourself.
CAUSE - The water is coming from the drain hole because the pressure valve at the top of the machine is blocked with calcium deposits through prolonged use without descaling sufficiently.
SOLUTION - Purchase a good quality coffee machine descaler. Sit the whole coffee machine in a tray or large oven tray so you can collect the overflowing descaler throughout the process, it's not economical to waste this solution. Remember to clean down and dry the coffee maker each time.
Use at least half strength descaler do not water it down more than 1:1
Follow the descaling process by inserting the yellow disc and holding the start button down for 3 seconds.
Repeat this process several times, recovering the fluid leaking in to the tray and cup or container. If you start to see small lumps being dispelled in to the cup try to remove these for further descaling.
After several cycles you should notice that the leaking or flow of water from the bottom drain hole becomes less until it stops. To force the dissolving scale out of the pressure valve try running the normal clean cycle but with the descaling solution, the flow is longer and will help flush the restriction.
After a number of descaling and clean cycles the leak or flow from the drain hole will have stopped, if not continue till it does.
Note: I ran cycles for about 2 hours with periods of rest to allow the solution to do its work.
Now the leak or flow has stopped clean out the reservoir and replace with clean water and run at least 4 clean and rinse cycles.
i hope this works for you and now enjoy your coffee.