The procedure we will be telling you can be used for storage medium of all drive types, whether they are USB, external Hard Drives or Flash drives. There are file systems however that allow for communications for both Mac and Windows but you would have to format them first. While the Mac OS can read the data present on the storage medium, it can’t write to it. The problem at hand is that the portable storage media, such as a USB flash drive or an External hard drive can’t be used on both OS because they use different file systems. We are also no strangers to the fact that this is an era of portability and versatility of data.