He reached for a dusty USB drive labeled Using the Microsoft Media Creation Tool, he had already turned it into a bootable lifeline. He plugged it in and navigated to the Boot Priority menu.

How to Format C Drive From BIOS: Step-by-Step Guide You cannot format the C drive from inside Windows while the operating system is actively running. To completely wipe your primary system partition, you must .

A: It was likely showing a legacy DOS command prompt. Very old operating systems (like Windows 98) allowed you to boot into a command prompt (C:) and type format c: . Modern computers use the NTFS file system and complex operating systems that cannot simply be wiped while active or through basic BIOS firmware. You must boot from an external source to format the main drive.

Executing a format will permanently delete your operating system, software applications, system preferences, and personal configuration data.

But by using the BIOS to boot from external media, you can easily format the drive. If someone tells you otherwise, they are either confused or referring to very old, non-standard systems (e.g., some 1980s DOS-era ROM BASIC).

If your motherboard is modern, look for a feature called "Secure Erase" in the BIOS Storage settings—it's a faster way to wipe SSDs without needing a USB [6, 9].