Created on: May 11, 2013
Last updated: August 25, 2015
This may be due to the drive format you're trying to use. The recommended format for OS X is Mac OS Extended (Journaled). Try the steps below to see if they resolve the issue.
1. Launch Disk Utility.
2. Highlight Qx2 drive icon. It should say something like "__TB OWC Mercury....".
3. Click the Partition tab.
4. From the pop-up menu choose 1 Partition.
5. Give your new volume a name (avoid special characters).
6. Under format choose "Mac OS Extended (Journaled)".
7. Click Options... and choose "GUID Partition Table", then click OK.
8. Click Apply and when asked if you want to partition click yes.