How to fix external drive not mounting issue on Mac without data loss?

Summary: Can't access important data when your external drive is not mounting on Mac? Just download iBoysoft Mac Data Recovery to recover data from unmountable external hard drives and fix external drive not mounting issue on Mac without data loss.

By Juno | Posted to Mac Data Recovery, updated on March 25th, 2019 |

"Since updating to macOS High Sierra, my Seagate 1TB hard drive can't be mounted by my Retina MacBook Pro (2014). It appears in Disk Utility but not in Finder or on the Desktop. In Disk Utility, I can't do anything but format it, which I do not want to do for there are still useful files on it. Is there any suggestion on the issue that external hard drive is not mounting? Can I recover data from this unmounted external drive?"

external drive is not mounting on Mac

It is such an annoyance if you find that you're unable to mount external hard drive on Mac computer, especially when you thought you can access data on this drive as usually but it just failed. Before you go crazy, you may be wondering why this external drive is not mounting on Mac because you didn't do anything abnormal to it. As a matter of fact, this problem could be caused by many factors, such as damaged file system, virus attack, unsafe ejection or any other improper operation.

No matter what the reason it is, the first and most important thing for you probably is recovering data from this unmounted external hard drive. The thing you concern is, how can you recover data from an external drive that is not even mounting? Don't worry, just get into the feasible solution step by step through this article.

Table of contents
1. Tips for fixing external drive not mounting issue
2. How to fix unmounted external drive without losing data?
3. Alternative suggestions on external drive not mounting problem

Tips for fixing external drive not mounting issue

For an external drive that is not mounted on Mac, it is possible to recover files from it indeed. But there are some things that you need to keep in mind, or you could lose the chance to get your files back.

• Do not format this external drive before recovering lost data

• Do not save anything new to this drive

The reason for such cautiousness is that any further operation is very likely to overwrite your original files and make them unrecoverable. The more files you covered by improper operation, the less opportunity you own to recover files from this unmountable external drive.

How to fix unmountable external drive without losing data?

You might have searched on Google and was told to reformat if you can't access data on this external drive. But you probably missed an important thing that reformatting will erase all your data on this drive. Thus, for users who have useful data on the not mounting external drive, make sure you have backed up all data previously, and if you don't have any backup, take this step-by-step advice to fix external drive not mounting issue on Mac without worrying data loss.

Step 1:Recover data from the unmounted external drive

As long as your external drive doesn't have any hardware problem, fortunately, you can retrieve your files with professional Mac data recovery software - iBoysoft Mac Data Recovery with no fuss.

iBoysoft Mac Data Recovery is a free external drive data recovery tool for Mac that can not only recover data from unmountable external drives, but also recover data from formatted external hard drives, recover data from inaccessible external hard drives, recover data from unreadable external hard drive, recover data from corrupted external hard drives. This external drive data recovery tool supports external hard drives, USB flash drives, memory cards, SD cards, and many other external storage devices. You can perform data recovery on macOS 10.14/10.13/10.12 and Mac OS X 10.11/10.10/10.9/10.8/10.7.

Tutorial for external drive data recovery on Mac with iBoysoft Mac Data Recovery

1. Free download and install iBoysoft Mac Data Recovery on Mac.

2. Launch iBoysoft Mac Data Recovery.

Recover data from not mounting external drive on Mac with iBoysoft Mac Data Recovery

3. Select the external drive that is not mounting and click "Next" button to scan for all lost data.

4. Preview the searching results, choose files you need, and click "Recover" to get them back.

Preview and Recover data from not mounting external drive on Mac with iBoysoft Mac Data Recovery

Note: You need to save the recovered files to another usable drive so that you will not erase them mistakenly in Step 3.

5. Have a check to ensure we have got all lost data back.

Step 2:Repair this unmountable external drive with First Aid

After successfully restored all lost data, you can set out to fix external drive not mounting issue on Mac. The first suggestion is First Aid in Disk Utility, which is a free repair tool that built in your Mac. Follow the instructions and you can correct various disk-related errors via this useful software errors.

1.Go to Utilities and launch Disk Utility on your Mac computer.

2. Click on "Show all devices" in View option and choose the unmountable external drive on the left sidebar.

3. Select First Aid in the top center and click Run.

Step 3:Fix the external drive not mounting issue by reformatting

If Disk Utility can't repair the disk and your external drive still can't be mounted in Disk Utility after you perform First Aid, your drive should have some serious errors like file system corruption that is beyond its ability. Therefore, reformatting is the most feasible way to fix external drive not mounting problem.

Disk Utility failed to repair external drive

Warning: Reformatting, as mentioned before, will erase all data on the external drive, make sure you have a copy of data backup or have recovered files from this unmounted external drive.

1. Launch Disk Utility.

2. Click the icon of your unmountable external drive on the left sidebar.

3. Click on the Erase button function on the top of the Disk Utility window.

4. Complete the related information (name, format, scheme), then click Erase button to finish reformatting.

Alternative suggestions on external drive not mounting problem

In case you miss anything necessary, you can also try the alternative fixes as following if your external srive is not mounting on your Mac computer.

1. Re-plug your external drive to another port or try another USB cable. A faulty connection, though it is foolproof, is often the key to fix the external drive not mounting issue, in that users always forget to check if the port is wobbly or if the cable is broken.

2. Manually mount this external drive in Disk Utility. Even though Apple has done a great work by automatically mounting your external drive once you connect it to your Mac, malfunction is an inevitable error, in this case, you can manually "Mount" your drive instead.

3. Check your Finder Preferences. When your external drive is not mounting on the desktop, you can open Finder, choose "Preference" (or press Control +, ) and check "External disks" both in General tab and in Sidebar tab to show your external drive on your Mac computer.

In a word, the external drive not mounting issue is solvable with the assistance of iBoysoft Mac Data Recovery, but for you, the most convenient and advisable way is to back up important files regularly.

Still have questions?