Hi, first thanks for the replies to the other thread. Right, ok here goes. I have a WD Passport external hard drive, formatted in NTFS which i used with a Windows laptop before switching to a mac, I installed the Paragon NTFS driver to enable read / write to and from the drive. The passport drive works fine with the mac, now when i plug it into a windows system it appears to be corrupted and it just doesnt open, I have tried uninstalling the driver from device manager, restarting and installing, also have made it "active" in computer management - disk management services. no luck thanks in advance to anyone who has any ideas.