I have WD external hard disk, which was working fine. Its MS-DOS formatted. I have downloaded a file in .mkv, which works fine, and isn't corrupted. Upon copying the 8 gb file, it says "The file is too big to be copied", whereas its only 8 GB being copied on 500GB disk. I tried formatting it. still nothing. What else can i do?
The HDD is formatted using FAT32 which has a known limitation of 4GB file size. You need to format it using exFAT which is supported by OS X and Windows.