Top Fixes For ‘Windows Was Unable To Complete the Format’ Error

Are you trying to format a USB drive such as Pen drive, memory card, etc. on a Windows system and getting the error ‘Windows Was Unable to Complete the Format’?

You may see this error while trying to format the drive if write protection is enabled on drive, or there are bad sectors, the drive is corrupted, drive’s file system is damaged, and so on.

You can try to fix this error by scanning the affected drive for malware or try formatting it by using any other working system.

If this doesn’t help, follow the methods in this post by using which you can fix the error triggered while formatting the drive.

But before you follow these methods to format the drive, make sure that you have backed up its important data or it doesn’t contain important data as formatting leads to data loss.

[IMPORTANT]: If you have critical data on your drive and you don’t have a backup, recover your data before fixing the error and formatting the drive by using a safe and effective data recovery tool like Stellar Data Recovery software.

Methods to Fix ‘Windows Was Unable to Complete the Format’ Error

Method 1: Disable Write-Protection

When a USB drive or SD card is write-protected, you can’t change files on the media; you cannot format the drive.

Check if the drive has a write protection switch (also called a lock switch). If yes, make sure the switch is set to write, not read-only.

If you don’t find such a switch, the drive may have software-based write-protection enabled.

To disable it, you can use Windows Diskpart utility which is the safest way of disabling write-protection.

  1. Connect the affected drive to a Windows system
  2. Press Windows+R keys

Run dialog box appears

  1. Type diskpartand hit Enter
  2. Allow the app to make changes (if prompted) by clicking Yes

This launches Diskpart utility in a Command Prompt window.

  1. Type list diskand press Enter

All the drives connected to your system will get listed with their respective disk number. You can find the disk number of a connected drive by referring to the Disk column in the list.

  1. Note the disk number of your affected USB drive
  2. Select the affected disk by typing the command select disk disk_numberand then press Enter

[IMPORTANT]: Replace disk_number with the actual disk number of the drive. For example, if disk number of the affected drive is 1, the complete command would be select disk 1.

  1. Enter the command attributes disk clear readonlyand then hit Enter.

This command would disable write protection on the selected disk.

  1. Next, type exit and press Enter to close the Diskpart window
  2. Remove the drive safely
  3. Connect it back again, try to format and see if the error is fixed

Method 2: Use Windows Error Checking Tool

The error checking tool on Windows is a tool with GUI. It checks disk errors and tries to fix them.

  1. With your drive connected to your system, open Windows explorer.
  2. Right-click the drive, and select Properties

3. Choose Tools tab

4.Click Check button

This tries fixing disk issues.

5. Once this process completes, remove the disk safely

6. Connect the drive once again and try formatting it.

Method 3: Use CHKDSK Command

Using chkdsk command is another way of fixing disk issues, file system corruption etc. You can use this Windows built-in utility to fix minor corruption of disk. If running chkdsk is able to fix disk corruption, you might be able to format the drive successfully without getting ‘Windows Was Unable to Complete the Format’ error.

[NOTE]: This command would work only with NTFS drives.

Follow the steps to run chkdsk command:

  1. Click Windows icon and type cmd
  2. Right-click Command Prompt that populates, and choose Run as administrator
  3. Allow the app to make changes by clicking Yes when prompted
  4. Type chkdsk /f /r h:and hit Enter

Where, h is the drive letter of affected USB drive connected to your system.

  1. Try formatting the disk after the chkdsk command has completely executed

Method 4: Use Windows Disk Management Utility

If you’re getting ‘Windows Was Unable to Complete the Format’ error while formatting the USB drive by using Windows File Explorer, try using Windows Disk Management Utility for formatting.

You can do it as follows:

  1. Press Windows+X key
  2. Choose Disk Management from the list
  3. Right-click the affected drive and click Format

[NOTE]: if you don’t see the Format option or if it’s disabled, click New Simple Volume

  1. Assign a Label, and select a File System
  2. Click OK for the prompts that follow

Check if the drive is formatted now.

Method 5: Use DiskPart command

Diskpart is a command line utility which you can use to format the drive in case it’s throwing ‘unable to complete format’ error.

Here’s how you can do it:

  1. Connect the affected external drive to a system (if not connected)
  2. Click on windows icon, type diskpart and hit Enter
  3. On the DiskPart window that opens, type list disk and hit
  4. Type select disk disk_number to select the disk which is unable to format

Replace disk_number in the above command with disk number of error throwing disk. The complete should look similar to select disk 1 if the affected disk’s number is 1.

  1. Next, type clean and hit

This removes existing partition and formatting from the selected disk.

  1. Type create part pri and hit Enter to create a primary partition on the disk you’ve selected for formatting
  2. To make this partition active, type active and hit Enter
  3. Type format FS=fat32 label=MyDrive quickand hit

This will give your drive fat32 file system and would label as MyDrive. You can choose a different supported file system and also choose any other label.

  1. Assign a drive letter to the drive by typing assign letter=Y and then hitting Enter

Doing this assigns Y as a drive letter to the affected drive. You can choose any other letter.

  1. Lastly, type exit and hit Enter

Following the above steps may help you format the drive with a specified file system, label, and drive letter.


Due to drive corruption, file system issues, bad sectors, or malware infection, you may encounter ‘Windows was unable to complete the format’ error while trying to format an external or USB drive.  You can first recover your crucial data (if not backed up) from the drive you want to format, and then follow the fixes mentioned in this post.