WD Elements 5TB WDBWLG0050HBK-EESN

Can I use this extrernal drive on my iMac OS X Yosemite? At the mone the only function I have on the hard drive is READ ONLY do I have to fomat the drive?

Thanks

Hello, Welcome to the WD Community. The WD Elements come formatted for Windows, you will need to format it for Mac to be able to use it.