Fix Seagate External Hard Drive Light Blinking but Not Working/Detectable Error

Problem: Seagate external hard drive light blinks, but not detected nor working on PC

It's no longer a new case that storage devices such as USB drive or external hard drive suddenly become undetectable by PC due to unknown reasons. Seagate external hard drive not working on PC with light blinking is one of the problems, which is still a troublesome case for most ordinary users. Right here in this article, you'll find 3 quick fixes and 3 effective methods to repair and fix Seagate external hard drive not working error without losing any data. 

Start with Three Quick Fixes

Don't worry about losing any data or cannot access to not working Seagate external hard drive anymore. Follow this article, we'll get your problem solved right now. 

1. Change USB port

Your very first move is to change the USB port and connect not working Seagate external hard drive with another new USB port to checkout whether the problem exists.

2. Turn on USB Root Hub

1. 1. Click Start, type: devmgmt.msc and hit Enter;
2. 2. Open Device Manager, expand Universal Serial Bus controllers;
3. 3. Right-click USB Root Hub, click Properties' and select Power Management;
4. 4. Uncheck Allow the computer to turn off this device to save power;

Repeat this process for each USB Root Hub in the list and reboot PC to see Seagate external hard drive on your PC then.

3. Clean up virus

If your computer and Seagate external hard drive are infected by a virus, it may cause the drive not detectable or unreadable.
The best solution for this issue is to use virus cleaning software to wipe out and clean up the virus on your drive and PC. Then you can reboot PC and retry to access the Seagate external hard drive now.

Proceed with Three Advanced Methods

1. Show all hidden devices

1. 1. Click on Start and type: devmgmt.msc and hit Enter;
2. 2. Click View in the device manager, then select Show hidden devices;
3. 3. Expand all notes by clicking on + symbol;
4. 4. If there are any greyed entries, right-click on it and select Uninstall;
5. 5. Reboot and try again.

2. Uninstall hard drive driver

1. 1. Click on Start and type: devmgmt.msc to open Device Manger by hitting Enter;
2. 2. Expand Universal Serial Universal Serial Bus controllers, right-click every USB device found there and select Uninstall;
3. Then check out whether any device show up as unrecognized or not:

• If the Toshiba external hard drive shows unrecognized, go to drivers tab and delete/uninstall the driver; 
• Then check out whether the external hard drive shows up in My Computer/My PC or not;
• If it doesn't show up, reboot or restart PC; 
• If it shows up but disappear later, repeat above steps and go to Disk Management, change the drive letter of your Toshiba external hard drive and reconnect it to PC to let PC detect it again.

3. Change registry

1. 1. Click on Start and type: regedt32 and click OK;
2. 2. Backup your registry by going to file and click export;
3. 3. On the left side, go to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318};
4. 4. If you see any upperfilter or lowerfilters at the right side, delete it;
5. 5. Then retry your external hard drive again.

Extra help: restore data after fixing the 'light on but not detected/read' error

After fixing the Seagate external hard drive not working issue, you may now try to open Seagate external hard drive to find your precious data.

If nothing is found, don't worry. Powerful hard drive recovery software from EaseUS will help you get lost data back. It's 100% working to retrieve lost data on storage devices with simple clicks:

1. Connect Seagate external hard drive with PC and free download EaseUS hard drive recovery software.

2. Active and run EaseUS Data Recovery Wizard and select location where your external hard drive is, click Scan.

3. Let this software to scan and find all data and other files on the external hard drive with Quick Scan and Deep Scan mode.
Preview and select found files, click Recover to restore all found files to a safe spot in PC.

Then save found data and files into another safe spot. Format and reset Seagate external hard drive to be reusable for storing data again.