How do I format an external HD to FAT32? I need to format an external HD to FAT32 so that I can use if for both Mac and PC. I need to copy some files from a PC (mostly powerpoint presentations and MPEG videos) so that I can use them on my Mac. Tried using the Mac OS disk utilities to reformat the HD but unfortunately, the drop down menu for this function only allows formatting of Mac OS and UNIX formats. What can I do? Don't really want to format the external HD (LaCie D2 quadra) using the PC because it is possible infected by viruses. By the way, I am still running my MBP on Mac OS 10.4.