Since updating to macOS Sierra, my 3TB WD external USB hard drive isn't being read or mounted by my Retina MacBook Pro (2014). It appears in Disk Utility but not in Finder or on the Desktop. In Disk Utility I cannot do anything but format it which I DO NOT want to do. Any suggestions or help?!
Lora asked for help on Facebook last Saturday. She saw her external USB hard drive in Disk Utility as "Not Mounted".
Subsequently, many friends said their external hard drives not mounted either.
External hard drive not mounted on Mac may happen to anyone. The reasons are varied. File system corruption is the most common reason that makes Mac OS X unable to mount external hard drive.
When external hard drive not mounted, data in that external hard drive will lose. But the data lost from it can be recovered with professional Mac data recovery software. iBoysoft Mac Data Recovery is highly recommended because it can safely and easily recover data from external hard drive that not mounted on Mac.
Recover data from not mounted external hard drive with iBoysoft Mac Data Recovery
iBoysoft Mac Data Recovery is an efficient and safe Mac data recovery software. It can recover data from not mounted external hard drive and unmountable hard drive with ease. It can recover lost or deleted data from hard drive, external hard drive, flash drive, USB stick and other storage devices on macOS 10.13 (High Sierra), macOS 10.12 (Sierra) and Mac OS X 10.11/10.10/10.9/10.8/10.7.
With 4 simple steps, you can recover data from external hard drive that not mounted on Mac.
Step-by-step tutorial to recover data from not mounted external hard drive
Step 1: Download and install iBoysoft Mac Data Recovery on your Mac.
Step 2: Launch iBoysoft Mac Data Recovery, and select the external hard drive that not mounted.
Step 3: Click Next button to scan all lost files.
Step 4: Preview the results, choose files you want to recover, and click Recover button to recover data from not mounted external hard drive.
Besides recovering data from external hard drive that not mounted, iBoysoft Mac Data Recovery can help you to recover data from unreadable external hard drive, recover data from corrupted external hard drive, recover data from inaccessible hard drive, recover data from invalid volume header hard drive, recover data from formatted drive, etc.
Way to fix the issue of external hard drive not mounted
After recovering data from external hard drive that not mounted, please reformat it in Disk Utility to fix the issue.
Step 1: Launch Disk Utility from Utilities.
Step 2: Click the icon of external hard drive that not mounted on the left part of the window.
Step 3: Click the Erase function on the top of the Disk Utility window.
Step 4: Complete the related information(name, format, scheme), then click Erase button.
After operating these steps successfully, the not mounted external hard drive can be used normally.
Still have questions?