How to fix usb not recognised​

A Universal Serial Bus (USB) device is an essential part of daily digital life used for everything from transferring files to charging devices, updating firmware, and expanding storage. However, encountering the frustrating “USB device not recognized” error can halt productivity, block access to important files, and spark panic especially if you believe the data may be lost. Fortunately, there are practical, step-by-step methods to fix this issue, whether it’s a corrupted flash drive, a faulty USB port, or a software conflict.

Chapter 1: Problem

1.1 What Does “USB Not Recognized” Mean?

The “USB device not recognized” error indicates that the operating system detects a connection to the USB port but fails to identify or communicate with the device. This is often accompanied by one of the following messages:

“The last USB device you connected to this computer malfunctioned.”

“Unknown USB Device (Device Descriptor Request Failed).”

The device doesn’t appear in File Explorer (Windows) or Finder (macOS).

1.2 Common Reasons for USB Not Being Recognized

Before jumping into fixes, it’s important to identify potential causes:

Corrupted or outdated drivers

Power supply issues

Faulty or damaged USB ports

Conflict with other connected USB devices

Drive corruption or file system errors

Malware or virus infections

Operating system glitches

Physical damage to the USB device

Chapter 2: Initial Troubleshooting Steps

Start with these basic checks to rule out temporary or obvious issues.

2.1 Restart Your Computer

A simple reboot clears temporary glitches that may be affecting hardware recognition.

2.2 Try a Different USB Port

Sometimes the port itself is faulty. Test all available ports, especially on the back of desktop PCs.

2.3 Test the USB Device on Another Computer

This helps determine whether the issue lies with the USB drive or your computer.

2.4 Use a Different USB Cable or Adapter

For external hard drives or devices requiring cables, a damaged cable could be the culprit.

2.5 Disconnect Other USB Devices

USB port power or bandwidth may be limited. Remove other USB devices and reconnect only the one you’re testing.

Chapter 3: Windows Fixes for USB Not Recognized

3.1 Update or Reinstall USB Drivers

Right-click the Start button and select Device Manager.

Expand the Universal Serial Bus controllers section.

Locate entries such as:

“Unknown USB Device”

“USB Root Hub”

Right-click and choose Uninstall device.

Restart your PC—Windows will attempt to reinstall the driver.

Alternatively:

Right-click and choose Update driver → Search automatically for drivers.

3.2 Scan for Hardware Changes

Open Device Manager.

Right-click your computer name at the top.

Choose Scan for hardware changes.

3.3 Enable USB Root Hub

Open Device Manager.

Under Universal Serial Bus controllers, right-click USB Root Hub → Properties.

Go to the Power Management tab.

Uncheck Allow the computer to turn off this device to save power.

Repeat for all USB Root Hub entries.

3.4 Disable USB Selective Suspend Setting

Go to Control Panel → Power Options.

Click Change plan settings → Change advanced power settings.

Expand USB settings → USB selective suspend setting.

Disable both On battery and Plugged in.

3.5 Use Disk Management to Assign a Drive Letter

Press Windows + X → Disk Management.

Look for your USB device.

If listed without a drive letter, right-click it.

Choose Change Drive Letter and Paths → Add.

Assign a letter and click OK.

3.6 Format the USB Device (Last Resort)

⚠️ Warning: This will erase all data. Use data recovery tools beforehand if needed.

In Disk Management, right-click the device.

Select Format.

Choose a file system (e.g., FAT32 or exFAT), check Quick Format, and proceed.

Chapter 4: macOS Fixes for USB Not Recognized

4.1 Restart and Reconnect

Disconnect the USB, restart your Mac, and reconnect after the reboot.

4.2 Check Finder Preferences

Open Finder → Settings (or Preferences).

Under Sidebar and General, make sure External disks is checked.

4.3 Use Disk Utility

Open Applications → Utilities → Disk Utility.

Look for your USB under External.

If grayed out, try to mount it manually.

Click Mount.

If it’s unmountable or corrupted, use First Aid to repair it.

4.4 Reset NVRAM and SMC

Reset NVRAM:

Shut down your Mac.

Turn it on and immediately press and hold Option + Command + P + R for 20 seconds.

Reset SMC:

For Intel Macs: Shut down → Unplug power for 15 seconds → Reconnect and restart.

For M1 Macs: SMC resets automatically on reboot.

Chapter 5: Data Recovery Before Formatting

If your USB is detected but inaccessible or corrupted, recover your files before formatting.

5.1 Use Recovery Software (Windows/macOS)

Panda Assistant

Panda Assistant automatically scans your USB device upon connection, identifying errors like file system corruption, partition loss, or damaged boot sectors. With one-click repair options, it can restore the USB drive to a working state without requiring advanced technical knowledge. The software supports a wide range of USB devices including flash drives, external hard drives, and memory cards, ensuring compatibility across the board.

If your files are still accessible but invisible or unreadable, Panda Assistant’s powerful data recovery module can scan the drive and safely recover documents, photos, videos, and more even from devices that appear blank or unformatted.

Chapter 6: Fixing Physical and Hardware Issues

6.1 Inspect the USB Device

Check for physical damage such as bent connectors, cracked casing, or burn marks.

6.2 Use a Powered USB Hub

Some drives need more power than certain ports provide. A powered hub can help stabilize the connection.

6.3 Use a Professional Repair Service

If the USB contains critical data and none of the above methods work, consider a data recovery lab.

Chapter 7: Preventing Future USB Issues

7.1 Safely Eject Devices

Always eject USB devices via the operating system to prevent file corruption.

7.2 Avoid Sudden Power Loss

Use a UPS for desktop PCs to avoid corruption during power outages.

7.3 Keep Drivers and OS Updated

Install updates regularly to avoid conflicts and bugs.

7.4 Perform Regular Backups

Use cloud services or external drives to back up critical data.

Chapter 8: Advanced Solutions for Tech-Savvy Users

8.1 Use Windows Command Line

Check disk integrity:

bash

CopyEdit

chkdsk E: /f /r /x

Replace E: with your USB’s drive letter.

8.2 Use Diskpart

Open Command Prompt as administrator.

Type:

bash

CopyEdit

diskpart list disk select disk # clean create partition primary format fs=ntfs quick assign exit

Be cautious: this will erase the entire USB drive.

Chapter 9: When to Replace Your USB Device

If you’ve exhausted all recovery and repair efforts, it may be time to replace the USB stick or external drive. Signs of terminal failure include:

USB not detected on any device

Loud clicking or buzzing sounds from external drives

Drive heats up rapidly

Frequent corruption despite reformatting