By Bryce / Last Updated September 6, 2019

Failed to format C drive in Windows 7

“I have a computer running Windows 7. Recently, I tried format my C drive due to certain reason, but I failed to format it within File Explorer and got the error message – “You cannot format this volume”. Is there one 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 File Explorer?

System partition C, is an active partition with 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 Windows environment. That is to say, you are not allowed to formatting C drive within Windows 7 File Explorer or Disk Management. But you can format C drive without booting OS from the system hard drive.

Two ways to format C drive that holds Windows 7

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

At this time, you can boot your laptop or desktop from somewhere else to format C drive that is installed with Windows 7. If you have no Windows installation CD/DVD, you can choose the first way illustrating how to format C drive with Windows 7 installed without CD/DVD; if you have Windows Setup CD/DVD or Windows 7 recovery USB drive, select the second way that presents how to format system drive with Command Prompt.

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

Format C drive that contains Windows 7 without CD/DVD

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 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.

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.

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 C drive with Window installation media

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

1. Insert Windows installation media into the computer and enter BIOS to boot computer from it.

(Take Windows 7 Setup 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”.

3. In the initial Windows installation screen, click on “Install now” button and wait for the “Setup is starting” screen over.

4. Read license terms and check “I accept the license terms” and click “Next”.

5. Choose Custom (advanced) between two types of Windows 7 installation.

6. In “Where do you want to install Windows” window, you can view all recognized partitions in computer. Click “Drive options (advanced)” and several drive options will appear.

7. Select C drive and click “Format”. You’ll be noticed that any data stored on the partition that you’ll format will be lost, click “OK” to start operation.

Or you can choose to format C drive from Command Prompt with Windows Setup CD/DVD by following steps below.

1. In the first “Installation Windows” window, click “Repair your computer”.

2. Select operating system and click “Next”.

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

4. 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.