Retrieving Your Files After Changing BIOS from UEFI to Legacy

The task of changing your BIOS from UEFI to Legacy to retrieve your files can be intimidating, especially if your system is now displaying 'Non-System Disk or Disk Error.' This article aims to guide you through the troubleshooting process, provide solutions, and offer advice on how to avoid similar issues in the future.

Understanding the Issue

First, it's important to understand why your system is displaying this error message. This usually occurs when the BIOS mode is changed from UEFI to Legacy without properly updating or configuring the new settings. If your system does not support UEFI, attempting to boot in UEFI mode can result in a 'Non-System Disk or Disk Error' message, as the system cannot find the necessary boot files.

Possible Solutions

1. Switch the BIOS Back to Legacy Mode

As a first step, try switching the BIOS back to Legacy mode. This should restore your system to a usable state, allowing you to access the BIOS settings and potentially retrieve your files.

Power off your computer. Long press the DEL key or another key (depending on your motherboard) to enter the BIOS setup. Navigate to the BIOS settings and change the boot mode from UEFI to Legacy. Save the changes and exit the BIOS setup.

2. Use a Bootable USB Drive for Repair

If switching the BIOS back to Legacy mode does not resolve the issue, you can try using a bootable USB drive containing tools that can repair the boot files. Here's how you can create a bootable USB drive:

Download and install a disk cloning utility like Rufus or Etcher on another computer. Insert a USB drive and use the utility to create a bootable USB drive using a Linux system image or a Windows repair CD. Boot from the USB drive in Legacy BIOS mode. Use the tool to repair the bootloader or reinstall the necessary files.

Advanced Troubleshooting

3. Clearing CMOS to Reset BIOS Settings

If the above steps do not resolve your issue, you may need to clear the CMOS. This can be done by following these steps:

Power off your computer. Locate the small jumper (usually labeled CLEAR CMOS) on the motherboard near the CMOS battery. Move the jumper to the clear CMOS position and hold it for several seconds. Return the jumper to its original position. Power on your computer and enter the BIOS setup. Reset the BIOS settings to the default values.

4. Downloading and Installing a New BIOS

In some cases, a corrupted or mismatched BIOS can cause issues. If clearing CMOS and resetting BIOS settings do not resolve the problem, you may need to download and install a new BIOS:

Identify your computer model and manufacturer. Va to the manufacturer's website and find the BIOS update utility. Download the appropriate BIOS update utility and the new BIOS file. Insert a USB drive, using a tool like Rufus or Etcher to create a bootable USB drive with the BIOS update utility. Boot from the USB drive in Legacy BIOS mode. Follow the on-screen instructions to flash the new BIOS onto your computer.

Prevention is Key

To avoid such issues in the future, always:

Backup your important files before making any BIOS changes. Refer to the official documentation or support resources of your computer manufacturer to understand the correct procedures for changing BIOS settings. Ensure that your system supports the BIOS mode you are trying to use.

Conclusion

Switching your BIOS from UEFI to Legacy can be a crucial step in retrieving your files. By following the steps outlined in this article, you can resolve the 'Non-System Disk or Disk Error' message and access your system again. Always stay informed about your system's requirements and follow best practices to avoid such complications.