Solved: SD Card Will Not Format in Windows

May 29, 2018

This article offers you effective ways to solve (micro) SD card not formatting in Windows, you can apply one or more solutions according to your own situation.

SD card will not format within Windows File Explorer

You may need to format (micro) SD card out the following reasons:

  • The SD card is newly purchased and unformatted. You should to format the SD card firstly in order to make use of it.

  • The SD card not recognized by your devices like Xbox One or PS3, you need to format it to be compatible with Xbox or PS3.

  • The capacity of the SD card is not fully shown. For example, 3TB SD card only shows 2TB in capacity.

However, when you connect your SD card to the computer that holds Windows system and format it within File Explorer, you may encounter the situation that the SD card will not format and you receive the error messages like “The disk is write protected or “Windows was unable to complete the format” etc.

SD Card Will Not Format

Possible causes of SD card not formatting in Windows

As we have mentioned, if the SD card is write protected, then you can’t format it. Besides, there are many other reasons that could cause SD card not formatting in Windows,, such as virus infection, bad sectors, incompatible file system or physical damage etc.

Solutions for “SD card will not format” in Windows

After realizing why Windows File Explorer unable to format SD card, it is time to learn the effective solutions listed as follows and you can take measures according to specific situation.

Remove write protection on SD card

If your SD card is unable to format due to write protection, try the following ways:

A. Check the lock switch of SD card adapter

Micro SD card or mini SD card needs to be put in SD card adapter that may have a write-protection lock switch. Check it and slide it to remove lock on SD card. Then, you can format the SD card within File Explorer.

B. Clear readonly using Diskaprt utility

1. Press Windows + R at the same time, type “diskpart” and hit “Enter”.

2. Type the following commands and every command comes with hitting “Enter “key.

  • list disk (list all disk connected to the computer)

  • select disk n, where n is the number of your SD card.

  • attributes disk clear readonly

After readonly is cleared, you can type “exit” to close the window.

Clear Readonly on SD Card

C. Change System Registry value

1. Input “regedit” in the Run box and hit “Enter”.

2. Navigate to the path listed below:


3. Double click “WriteProtect” option and set the value to 0.

Remove Write Protection

PS.: If there is no StorageDevicePolices folder under Control folder, you can right click on “Control” and go to “New”>“Key”. Name it with StorageDevicePolicies and then open it. Then, right click on the white space at the right-hand pane and navigate to “New”> DWORD (32-bit). Then, name it with WriteProtect and double-click on it to check the Value data.

Create a new partition via Disk Management

When the SD card is not allocated, you can’t format it within File Explorer. And you could see the SD card present in the form of an unallocated space in Disk Management. In such case, you need to create a new partition on the SD card.

1. Open Disk Management

2. Right click the unallocated space and choose “New Simple Volume”.

3. Follow the New Simple Volume Wizard to create a new partition.

Format SD card with Disk Management or 3rd party partition manager

If SD card is not shown in File Explorer due to its unrecognized file system, try to format it by following the ways listed below.

A. Format SD card using Disk Management

1. Open Disk Management

2. Right click the SD card partition and choose “Format”.

3. Choose a file system for SD card and click “OK”.

Format SD  Card Disk Management

B. Format SD card with third party software

If Disk Management has no option of file system that you need to format SD card to, you can apply third party software like AOMEI Partition Assistant to format it. It offers more choice of file systems. Apart from NTFS, FAT32, exFAT.It offers you more file systems for SD card partition. Apart from NTFS, FAT32, exFAT, it allows you to format SD card to Ext2, Ext3 and Ext4. What’s more important is that it allows you to format drive over 32GB to FAT32. The detailed steps are listed as follows:

Step 1. Free download this SD card format tool, install and run it.

Step 2. Right click the partition on the SD card and choose “Format Partition”

Format SD Card AOMEI

Step 3. Choose file system in this pop-up window. You can add Partition Label and adjust cluster size if you want.

Choose NTFS File System

Step 4. Return to the main interface. Review the pending operation and click “Apply” to complete format.


Run anti-virus software to scan SD card

If the SD card is infected by virus, it will unable to be accessed by other program. At this point, you can run third-party anti-virus software to fully scan the SD card, thus you can know whether it is infected.

Run Chkdsk utility in Diskpart

If the error –Windows unable to complete the format is caused by bad sector, you can run CHKDSK utility check it. The steps are listed as follows:

1. Run Command Prompt as administrator.

2. Input “chkdsk n:/f”, where “n” is the drive letter of the SD card partition.

3. Input “exit” to close the window.


PS.: If you are not familiar with Diskaprt command lies, you can check bad sector via AOMEI Partition Assistant.


When your SD card will not format within Windows File Explorer, you don’t have to try every methods mentioned above, just choose one or more ways to settle this issue quickly and effectively. And what you need to note is that if your SD card is damaged physically, the solutions aforementioned may not be helpful.