An external hard drive that keeps disconnecting and reconnecting may have a faulty cable, insufficient power, sleep-related issues, or failing hardware. Whether you use Windows or Mac, start with the checks below. They also apply to external USB SSDs.
1. Check the USB Connection and Power
Try a different USB data cable and another port on your computer. Connect the drive directly, bypassing any USB hub, dock, or adapter when possible.
If the drive requires external power, check its power adapter. Disconnect unused USB devices to reduce power demand. These checks follow Microsoft’s USB troubleshooting guidance.
2. Check Whether Sleep Triggers the Disconnect
If the drive disconnects after inactivity, temporarily keep your computer awake during transfers or recovery scans:
- Windows 11: Open Settings > System > Power & battery and adjust the sleep timeouts.
- Mac: Open System Settings > Battery > Options or Energy, depending on your Mac. Adjust the sleep settings and turn off Put hard disks to sleep when possible, if available.
Restore your preferred settings after testing.
3. If It Disconnects During Recovery, Create a Disk Image
If the drive remains readable but disconnects during a Disk Drill scan, consider creating a byte-to-byte backup first.
Save the image to a separate, healthy drive with enough free space for the source drive’s full capacity, plus extra room. Then scan the completed image instead of repeatedly scanning the original drive.
If imaging repeatedly fails or the drive becomes increasingly unstable, stop and contact a recovery specialist.
4. Check for File System Errors After Securing Your Files
Once your data is backed up or recovered and the connection is stable, check for file system errors using Windows Error checking or Disk Utility’s First Aid on Mac.
These tools address file system problems. They cannot repair physically damaged hardware. Avoid formatting the drive while you still need to recover files.