USB flash disk cannot be formatted

When a USB flash drive cannot be formatted, it can be frustrating, especially when you need to access or reuse the device. This issue is relatively common and can occur for several reasons, such as physical damage, software corruption, or security settings. 

1. Understanding the Issue

When a USB flash drive is working correctly, formatting should be a straightforward process. However, users sometimes encounter an error message like “Windows was unable to complete the format” or “Write-protected.” In such cases, it’s essential to identify the root cause of the issue before attempting further action. Common signs of a USB drive that cannot be formatted include:

The drive shows up in File Explorer but fails during the formatting process.

The drive is inaccessible, or an error message states that it’s write-protected.

The flash drive does not appear in Windows File Explorer, but it may appear in Disk Management.

2. Causes of the Problem

Several factors can prevent a USB flash drive from being formatted. Below are the most common causes:

a. Physical Damage

USB flash drives are susceptible to physical damage due to their portable nature. The internal components can be damaged by bending, dropping, or exposure to water or extreme temperatures, leading to problems like unreadable sectors, inability to format, and data loss.

b. Corrupted File System

If the file system on the flash drive becomes corrupted due to improper ejection, power surges, or malware, the drive may become unresponsive. In some cases, the corrupted sectors on the drive can cause Windows or macOS to fail during the format process.

c. Write Protection

Some USB drives come with a physical write-protection switch that prevents any modifications, including formatting. Even if the switch is not present, software-level write protection might be activated accidentally or through third-party security tools, preventing the user from formatting the device.

d. Drive in Use

If the USB drive is being accessed by another program or process, Windows or another operating system might prevent formatting. This is especially common when the drive contains system or program files that are in use.

e. Bad Sectors

Over time, flash memory in USB drives can wear out, leading to bad sectors. If these bad sectors are located in critical areas, the drive may not allow formatting, resulting in an error. Bad sectors usually indicate that the drive is nearing the end of its life cycle.

f. Driver or Firmware Issues

Sometimes, formatting issues can occur due to outdated or corrupted USB drivers or firmware. This problem is more prevalent in older drives or computers.

3. Troubleshooting Steps

Before attempting any drastic measures, it’s essential to go through some basic troubleshooting steps to determine the exact problem. Here are steps to identify and resolve issues preventing a USB flash drive from being formatted:

a. Check for Physical Damage

Examine the USB drive for any visible signs of damage.

Test the drive in different USB ports or on different computers to rule out connectivity issues.

If the drive appears physically damaged, data recovery services might be needed.

b. Check for Write Protection

If your USB flash drive has a write-protection switch, make sure it is turned off.

You can also check the software-level write protection using Windows:

Press Win + R, type regedit, and hit Enter.

Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\StorageDevicePolicies.

If the key “WriteProtect” is set to “1”, change it to “0” and restart your computer.

c. Use Disk Management Tool

Open the Disk Management tool in Windows by pressing Win + X and selecting Disk Management.

Locate your USB drive, right-click on it, and choose the “Format” option. This will allow you to try a more controlled formatting process.

If the USB drive appears as “RAW” in Disk Management, this may indicate a corrupted file system.

d. Disable Processes or Services Using the Drive

If a program or service is accessing the drive, it may prevent formatting. Close any open programs, especially file explorers or backup software, and try formatting again.

You can also use the Task Manager to end unnecessary tasks or restart your computer to free up the drive.

e. Check for Bad Sectors

Open Command Prompt (Admin) and type the following command:

bash

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chkdsk X: /f

(Replace X with the USB drive letter). This command checks and fixes file system errors, which may help make the drive formatable.

4. Advanced Solutions

If the basic troubleshooting steps do not resolve the problem, you may need to take more advanced actions:

a. Using Diskpart Command (Windows)

Diskpart is a powerful command-line tool in Windows that can help manage disk partitions and perform formatting operations that the regular File Explorer or Disk Management cannot.

Steps:

Press Win + R, type cmd, and hit Enter.

In Command Prompt, type diskpart and press Enter.

Type list disk to display all connected drives.

Find your USB flash drive from the list and note its disk number (e.g., Disk 1).

Type select disk X (replace X with the disk number).

Type clean to remove all partitions on the disk.

Type create partition primary.

Type format fs=ntfs quick to format the drive in NTFS format (you can use FAT32 or exFAT as needed).

b. Third-Party Formatting Tools

Some third-party utilities can handle stubborn formatting tasks better than the built-in operating system tools. These programs can bypass certain restrictions or provide more advanced formatting options. Some popular tools include:

HP USB Disk Storage Format Tool

EaseUS Partition Master

MiniTool Partition Wizard

These tools often offer additional functionality, like the ability to scan and repair bad sectors or partition recovery, which can be useful in severe cases of corruption.

c. Using Linux for Formatting

If Windows or macOS fails to format the drive, you can try using a Linux distribution. Linux often has better support for recovering or formatting stubborn drives.

Boot into a live Linux environment (e.g., Ubuntu) and use the GParted tool to try formatting the drive:

Install GParted: sudo apt install gparted.

Launch GParted, select the USB drive, and attempt to create a new partition table and format the drive.

5. Prevention Tips

Once the USB flash drive is formatted, taking steps to prevent similar issues in the future can save you from a repeat scenario:

a. Safely Eject the USB Drive

Always use the “Safely Remove Hardware” option before unplugging the USB flash drive from your computer. This ensures that any ongoing read/write operations are completed and reduces the risk of file system corruption.

b. Regular Backups

If your USB drive contains critical data, consider backing it up regularly to another drive or cloud storage. This way, if the drive becomes corrupted or unresponsive, you won’t lose important files.

c. Avoid Overuse

USB flash drives have a limited number of read/write cycles. If you frequently use the drive for transferring files, it may wear out faster. Avoid overuse by transferring files to a more reliable long-term storage option, such as an external hard drive or SSD.

d. Keep Your System Protected

Malware can corrupt USB flash drives. Keep your antivirus software up-to-date, and avoid plugging your USB into untrusted or public computers.

e. Choose Quality Drives

Purchasing USB flash drives from reputable manufacturers ensures a longer lifespan and better protection against common issues like file system corruption and bad sectors.