I have a MBA(2013). I can't seem to modify contents on a FAT32 HDD, if the HDD was originally FAT32 formatted on a Windows PC.(any Windows PC or laptop) The MBA can read or play the files just fine, however. I've tried this on a number of portable USB HDD.(either small 2.5" ones that are powered by USB, or larger 3.5" ones that require AC power adapter) Nothing seems to work.... as long as the HDD was originally formatted to FAT32 on *any* Windows PC, my MBA cannot modify anything on the drive. What am I doing wrong? Thanks for your help!