Why does my bread collapse in my bread machine? I have a bread machine and when I follow the recipes in the included booklet that came with the machine, the bread rises for about an hour, but the collapses back on itself and comes out rock hard and, usually, undercooked (doughy). I've tried adding flour, which helped a little, but didn't cure the problem.  When I bake bread in the oven (hand-kneading, etc.) it comes out just fine.

Some additional info: I've had similar problems with chocolate-chip cookies.  Recipes that work perfectly for other people collapse in our kitchen (even the recipe from the Nestle chocolate chips package).  My only theory is that since we live one block from a very large lake the air is somehow more humid, or dense, or something.  Adding almost twice as much flour to the cookies has make them stay up, but now they taste "cakey."

Does anyone know what might be going on and what I could try to help the problem?  I'm stabbing in the dark, since I don't know the science behind what's going on.
It may be because of the type of yeast being used.  Quick-cooking bread machines (1 hour cycle) typically requires "instant" yeast which rises much faster.  Standard-cooking bread machines (2-3 hour cycle) need regular yeast, which is active longer.  It sounds like you're using instant yeast in a standard recipe; thus the yeast stops working before the bread machine gets to the second rise cycle.  Under-cooking may be because the resultant dough is denser than the machine expects, thus doesn't heat through in time.

Unfortunately the trade names for "Regular Active Dry" yeast and "Instant Dry" yeast can be very confusing.