I have those disallows in the robots.txt for some months and has not stopped this
It is in the root of the domain.
Does this txt file have to be located somewhere else ?
yes, it must be located in the web root directory. to test if it's in the right place, open it in a web browser like this:
http://mydomain.com/robots.txt . if it doesn't appear, then it's in the wrong place.
