DFX & PDF

Hi.  I'm having 2 seperate import problems in Coreldraw X5 in Windows 7.  The first one, and the one I need to fix immediatly is, every time I try to import a dfx file, the program crashes.   The other which is less important right now is, a lot of times when I try to import PDF's I get an error message that says the file is corrupt.  Any help please, especially on the dfx problem.

Thanks,

Dom