I have two computers one with Windows 7 32 bit and the other with Window 7 64 bit. I use an HP Pro 8500 printer networked to communicate with both computers. I get onto a my financial web site and print my statements. On the Windows 7 32 system when I open the PDF to print I can get to the properties and select Duplex and it works great. On the Windows 7 64 bit system I select my statement to print the PDF but cannot select the properties button to select duplex. I can duplex other types of documents on both 32 bit and 64 bit but not the PDF's.