@ DJ AC > You should first make sure all your content on the drive is backed up on another drive, or on your computer. The you have to open "Disk Utility" found in your "Utilities" folder in the "Applications" folder. Once you have "Disk Utility" open, you should select the hard drive from the left pane. You can select either the title you gave the drive, or it's original title. Then select the "Erase" selection near the top middle section. Once you have selected that, choose the drop down list for "Format" and select "MS-DOS (FAT)" or (FAT32) if different. Once selected, choose your new title for the drive and click "Erase". This will then erase everything on your hard drive.
See screenshot below for example.
After all of that, you can re-load all of your music and files back onto your hard drive.
The reason it is not working is because it is programmed for Mac only. As Mac OS Extended. This means it will only work on a Mac computer. However, FAT32 or FAT works on Mac and PC, and therefore will connect to the CDJ's. The only downside to having to use FAT is that you cannot transfer a single file over 4.0GB. Doesn't happen very often, but you would need a separate drive for this purpose.
Let me know how it goes and if you have any more troubles.
Foster