Custom hotkeys don't get loaded on startup.

I made some custom hotkeys for Blender. However, every time I load Blender they are reset. I tried “Save as Default” in the preferences as well as “Save User Settings” in the File menu. None of these worked. I have to always manually load my hotkeys configuration file from “Import Key Configuration…” in the User Preferences every time I start Blender. How can I fix this?