By Bryce / Last Updated November 26, 2020

Failed to format C drive in Windows 7

“I have a computer running Windows 7. Recently, I tried to format my C drive, but I failed to format it within File Explorer and got the error message – “You cannot format this volume”. Is there one who can tell me how to format C drive in Windows 7? Thanks for your help!”

You Cannot Format This Volume

Why cannot format C drive within Windows 7?

System partition C is an active partition with the operating system installed. On a hard drive, only one partition can be set as active partition and the partition cannot be formatted or deleted within the Windows environment. That is to say, you are not allowed to format C drive within Windows 7 File Explorer or Disk Management. But you can format C drive without booting OS from the system hard drive.

Format Windows 7 C drive without CD/DVD

It’s not an easy task to format C drive holding Windows 7 operating system. As above covered you are unable to format it directly via File Explorer or Disk Management within Windows like formatting other drives.

If you have no Windows installation media, you can give AOMEI Partition Assistant Standard a shot. It is compatible with Windows 7/8/8.1/10, XP, and Vista, allowing you to make a bootable USB drive easily. You can boot your Windows 7 laptop or desktop from the bootable USB drive created by AOMEI Partition Assistant Standard and then you can format C drive just within three steps.

Note: As formatting will erase all data on the C drive, you can back up it at first if you don’t want to lose data on it.

Stage 1. Create Bootable USB drive

1. Connect a USB drive to a working computer running Windows and free download AOMEI Partition Assistant Standard on the working computer.

Download Freeware Win 10/8.1/8/7/XP
Secure Download

2. Install and run the software. In the main interface, click “Make Bootable Media” and do as the next prompts to create a bootable media.

Stage 2. Boot your Windows 7 computer from the created bootable USB drive

1. After creating bootable media, connect it to your Windows 7 computer whose C drive need to be formatted and boot the computer from it.

Boot from USB

2. Then, you can access the main interface of AOMEI Partition Assistant Standard.

Stage 3. Format system partition with Windows 7 installed

Step 1. Right-click the C drive and choose “Format Partition”.

Step 2. Choose a file system for C drive based on your demand and click “OK”.

Partition Label

Step 3. Here you can confirm your operation and click “Apply”>“Proceed” to implement it.

PS.: This way can also be applied to format C drive with Windows 10/8.1/8 installed.

Format Windows 7 C drive from Command Prompt

Supposed that you have Windows Setup CD/DVD, you can format Windows 7 C drive from Command Prompt. Have a look at how it works:

Note: Formatting will get rid of all data on the C drive, you can back up it in advance.

1. Insert Windows installation media into the computer and enter BIOS to boot your computer from it. (Take Windows 7 Setup CD/DVD as an example)

2. Waiting for “Windows is loading files…” and “Starting Windows” screens to finish. In the pop-up window, select “Language to install”, “Time and currency format” and “Keyboard or input method”. Then, click “Next”.

Choose Language

3. In the “Install Now” window, click “Repair your computer”.

4. Select operating system and click “Next”.

5. In the System Recovery Options window, choose “Command Prompt”.

Access Cmd Win7

6. Type “format c: /fs:ntfs” and hit “Enter” key

Wrap things up

Now, you should have your answer about how to format C drive in Windows 7. Make your decision based on your need.

What’s more, apart from formatting C drive, AOMEI Partition Assistant Standard allows you to extend or shrink C drive without data loss. And you can get more features like securely erasing SSD, converting system disk into GPT without data loss, and so on, if you upgrade it to AOMEI Partition Assistant Professional.