I've not tried this exact thing, but have done something similar. Derive a class from CFileDialog. At the end of the OnInitDialog() method, post a message. In the handler for that message, call ShowWindow(..., SW_HIDE) on the control you want to hide. If you are not using MFC, you can do the same thing using GetOpenFileName(). Just specify a hook procedure in the lpfnHook member variable. In the hook procedure, handle the WM_INITDIALOG by posting the same message as mentioned before. Hopefully this will solve your problem, or at least point you down the right path.
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