It is possible to modify, erase all stored data in this volume. NTFS for Mac OS X is a software that allows detecting an NTFS storage device with a Mac OS.But on you MAC, you will only able to read (open/copy) the contents of NTFS file systems, you will not able to perform any write operations like cut/delete. So, there is no issue on your Windows PC in accessing the external hard disk and performing read and write operations. As most of the regular external hard disks by default comes with NT File System (NTFS), which is the default file system of Windows. If you have Windows PC and as well a MAC and you often rely on external hard disks to store or transfer large files, then it could be a real pain for you.
