I am trying to get my 10 week old cocker spaniel used to being combed/brushed, but whenever I bring out the comb or the soft slicker brush (supplied by the breeder) he runs a mile and starts barking. Any suggestions please.

why not start it off with a grooming mit or one of the rubber zoom groom brushes, nice soft rubber bristles to get him use to being brushed. You can progress to a slicker once your puppy will sit still to be brushed. Using a reward for a moment of brushing and then building it up can improve your dogs willingness. My dogs hate being brushed, but I simply put a slip lead on before the brushes come out, they have no choice and resign themselves to their fate, if they see a brush first then they are off.

Ok this may seen rather harsh, but he needs to be groomed, if not when he is older he will need clipping and painful brushing of knots out. What I would do is put a rubber mat or towl on a table and make him stand still and be brushed. Give him lots of fuss and cuddles whilst he is being groomed then have a game when its finished. If you do a small bit everyday then it will work better at getting him used to it rather than one long session once a week. Good Luck!