


The file system issue is the most apparent cause of your external hard drive's detection but unable to be opened. Older external drives with USB 2.0 ports have a design issue that necessitates a slow connection. If your Mac cannot recognize the external hard drive, try carefully plugging it in. To resolve the problem, replace the cable. Other causes could be a wrong power source, a defective cable, or a corrupted or damaged drive.Īnother potential explanation for the external drive's failure to be detected by your Mac is a frayed or loosely attached USB cord. You'll need to use Disk Utility to format your drive differently in this situation.

Thus, the most frequent problem is improper drive formatting. To recover files from the external drive that's not mounting on Mac, do the following:įirst, free download, install and launch iBoysoft Data Recovery for Mac.Because the external hard drive is formatted in an unsupported format by macOS, such as NTFS, HFS+, or another, your external hard drive cannot be read on a Mac. If First Aid failed to resolve the issue, then your external drive should be damaged a lot, the last fix you can try is to reformat it.īut reformatting will erase all the data on this drive, so it's recommended to recover files from the external drive with a data recovery tool first, here we recommend iBoysoft Data Recovery - a professional external drive data recovery software, capable of recovering files from corrupted external hard drives, SSD, SD cards, and USB drives on Mac. When you see the error appearing on your Mac, using Disk Utility First Aid to repair it at once. It means that there may be some problems on the drive and you can't access photos, videos, documents, or other files on the external hard drive. The error usually occurs when you click the Mount option in Disk Utility.
