I’ve tried erasing and reformatting it to no avail. It’s currently exFAT with a GUID Partition Map, using it on a Mac. I’ve never been able to get it to show the full 10TB. Haven’t found this issue anywhere else so this is my last ditch effort at getting this thing to work properly.
Please provide the exact model# per the information label on the device.
Also, download and run WD Drive Utilities software and look at the drive with that.
https://support-en.wd.com/app/products/product-detail/p/267#WD_downloads
Compare the detected model# and serial# with what’s on the label.
the model number on the casing is WDBCKA0100HBK-NA. I will download that and report back, thank you
Geez I feel dumb I just shucked it and it says 4000 GBs. It was a gift from my brother so he must have mixed up a few harddrives. Thanks for your help anyway!
Well, that part number should be 10TB. So we still need to know what’s wrong where. 
Did Drive Utilities give a different model number?
