How to reformat an external SSD or HDD that is marked readonly

To low-level format and repartition an external SSD or HDD using diskpart, follow these steps to wipe the drive and remove the write protection:

1. Open Command Prompt as Administrator:

   • Press Win + S, type cmd, right-click “Command Prompt,” and select “Run as administrator.”

2. Run diskpart:

   • Type diskpart and press Enter.

3. List disks:

   • Type list disk and press Enter. Identify your SSD (e.g., Disk 1).

4. Select the SSD:

   • Type select disk X (replace X with the disk number of your SSD, e.g., select disk 1) and press Enter.

5. Remove write protection:

   • Type attributes disk clear readonly and press Enter.

6. Wipe the drive:

   • Type clean and press Enter. This removes all partitions and data, freeing the full drive.

7. Create a new partition:

   • Type create partition primary and press Enter.
   • Type format fs=ntfs quick and press Enter to format as NTFS.
   • Type assign and press Enter to assign a drive letter.

8. Exit diskpart:

   • Type exit and press Enter.

The SSD is now wiped, formatted, and ready for use. You can verify it in Disk Management or File Explorer.