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When you try to format a USB stick or SD memory card you may receive the message “Windows was Unable to Complete the Format”. This guide will show you how to resolve this error. First, let’s explore the causes of this error.
Possible Causes of this Error Message
The following could cause “Windows was Unable to Complete the Format” error:
- USB Stick or Memory card may be write-protected
- USB Stick or Memory Card may have bad sectors
- Memory card or USB Drive may be damaged
- Memory card or USB Drive may be infected by a virus
Fix 1: Make the Drive Writable
If you are not able to format your USB flash drive, it may be write-protected. To check whether your drive is Read-only and make it writable, follow the steps below:
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- Right-click the Windows logo on your task bar. Then select Run.
- When Run opens, type diskpart. Then click Ok. On the User Account Control, click Yes.
- Diskpart prompt opens as shown below.
- On the DISKPART> prompt, type list disk. Then press the Enter key. This will list all disks in your computer.
My USB flash drive is Disk 1. Use the size of your USB stick to determine the Disk #. Once you identify your USB stick Disk #, proceed to the next step.
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- Next, select your USB drive with the select disk command. Since my drive is Disk 1, my command is select disk 1.
- The next step is to check whether your disk is Read-Only. To do this use the attributes disk command.
From the information displayed, my USB disk is Read-only. It means it is NOT writable. As I mentioned at the beginning of this guide, this may result in “Windows was Unable to Complete the Format” error. Clearing the Read-only attribute could fix this error.
- Next step, is to clear the Read-only attribute using the command attributes disk clear readonly. Now, if you run the attributes disk command, the disk is no longer write-protected. See the image below for confirmation.
If you format your drive now, “Windows was Unable to Complete the Format” error should not show up. Also, you should be able to format your USB stick successfully.
Fix 2: Format the Drive with Diskpart
The next option that should fix the error is to format your drive with Diskpart.
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- Open Diskpart using the steps described earlier. Then type list volume command to list all available volumes (partitions) on your computer.
From the image above, my USB flash drive is Volume 3. Also important to note this: if your USB drive has issues, the Status will NOT be Healthy.
- Next, you need to select the volume. Type Select Volume # (replace # with your volume #) then press Enter. My command is Select Volume 3. Next, type format fs=fat32 and press Enter. Wait for the format to reach 100%. Depending on the size of your disk and problems with it, format may take some time to complete.
fs=fat32 tells Diskpart to format the disk with Fat32. You could use fs=ntfs to format with NTFS.
Make sure you selected the right volume before you run the format command. If you run Format in the wrong partition, this may be destructive to your computer.
Fix 3: Format the Drive with Disk Management
Another way you could fix this error is to format the disk with the Windows Disk Management tool.
Follow the steps below to open Disk Management and format your USB drive with it:
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- Right-click the Windows logo left of your task bar. Then click Disk Management.
- From Disk Management, right-click the partition beside the memory card or USB stick you wish to format then select Format.
Fix 4: Format the Drive with a 3rd Party Disk Tool
The last option to fix this error message is to use a 3rd party disk/partition tool to format the disk.
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There are a number of disk partitioning tools but I use the one called AOMEI Partition Assistant. Download and install this tool using this link.
To format your SD card or USB drive with AOMEI Partition Assistant, follow the steps below:
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- Open AOMEI Partition Assistant Standard Edition. You can open from the desktop shortcut or by searching for the program on your computer.
- If you receive a User Account Control prompt, click Yes. The tool will open.
If your disk has bad sectors, you may be able to fix it with the partition assistant.
- To see options available for managing disk with the partition assistant, right-click the disk.
When you right-click the disk, you have the following options that could fix problems with your drive:
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Rebuild MBR: If surface test reports that you have bad sectors, or other problems, using Rebuild MBR could fix the problem. This tool could also resolve the “Windows was Unable to Complete the Format” Error.
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- 【What You Get】16 GB USB Flash Drive Thumb Drive, The default format of the usb storage flash drive is FAT32.
- When you finish disk recovery tests, right-click the partition. Then select Format Partition.
Conclusion
There you have 4 ways you can fix “Windows was Unable to Complete the Format” error. Hopefully, one of these will resolve the problem with your USB stick or SD card.
If you were able to fix this error with the steps in this guide, kindly spare a few minutes to share your experience using the comments form (“Leave a Reply”) at the bottom of this page.
Alternatively, you can respond to the “Was this page helpful?” question below.
Finally, you may also find our Windows 10 Fix-it guides helpful.
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