When I noticed water damage to the baseboard and door trim, I called a contractor. On inspection he noticed the threshold was raised in the center sloping to the sides. In taking the trim and threshold off he saw how improperly the door was installed, it wasn't even level. To compensate for the fact it wasn't installed properly thy used caulk to try to level, over a 1/2 inch of caulk was used. It has taken 7 years for the water to get through and under the rubber seal the protects the sill plate. Luckily the sill plate although very wet, it had not rotted enough that it had to be replaced. The door is now level because my contractor had to totally remove the door and reinstall it. Now it opens properly and the lock works with forcing.