I am seeing a strange behavior with the Caption property of IDockableWindowDef. I have implemented IDockableWindowDef. I notice that the Caption of the window doesn't change even if I return a new value for the caption from the implementation. I have to unregister the dll, run ArcMap, re-register the dll, and then run ArcMap again - then only I see that the new caption is displayed in the caption area of the dockable window. I place a break point in the Caption property implementation of my class, and I see that the break point is only hit the very first time the ArcMap is run after registering the dll. After that if I change the Caption value in the code, the break point is never hit again unless I carry out the above steps I listed. Can anyone explain this? Am I missing some step or doing something wrong?