Hey guys. Due to me being one of the more Tech Savvy people in school the teachers that teach my classes usually ask me if they have an issue. Now this I got really stumped by. My teacher has a 500 GB External HDD that works fine on her windows 7 Dell laptop. However when she goes home and plugs it in to her mac book it says the drive is read only. Now I checked the Drives properties and it's all clean no read only. So is there anyway to solve this. The drives format is NTFS naturally due to it being a large drive.