Does all purpose f flour have bicarb or baking powder in it. We have flour here we call self raising and that has some bicrb of baking owder added in. We also have plain flour which diesn't have those. the bread flour has a different structure which has longer chains of protein and is therefore more elastic allowing the bread to rise and hold the air bubbles.
Check the freashness of the ingredients. if using yeast from the firdge check you don't have to let it come to room temp before adding tot he machine.
I agree check the manual. the "mess" will be the clue. For example if you make a hoceky puck you usually have a lack of yeast problem.
yeast is a living organisum and the water has to the the right temp when it goes in. too cold and it won't be able to activate the yeast enough, too warm and it will not work either. Too much sugar poisns the yeast and too little isn't enough to activate it all. Baking is science not art so follow the recipe exactly and make a note of what you do. the other thing that can affect it is the temp and humidity of the room in whcih the machin is operating.
Lots of variables but keep trying. Home baked bread is just divine. I just wish it didn't have such an effect on my waistline!
becks