When you start your computer, an error message saying “error loading operating system” appears on black screen, stopping you from using the system. This issue usually occurs, when you start your computer after installing an operating system or due to sudden power failure. It can also occur after a system crash or system restart.
Reasons behind “error loading operating system” issue
Normally when your system boots, the BIOS is responsible for loading the operating system from the hard drive. BIOS loads the first sector from the hard drive and passes the control to MBR. After this, MBR tries to load the sector from active partition, but if the sector is outside device sector count or it is not a verified sector, it results in MBR displaying the above error. The following are some of the most common reasons behind this error:
- Hard drive partition damaged due to Disk write error, virus attacks or sudden power cut can cause this error.
- When operating system files and folders are damaged, the OS cannot access the system files to boot properly.
- When multiple hard drives are connected to the laptop, the primary hard drive containing the OS might not get detected.
- The System BIOS not supporting the hard drive.
- A corrupt hard drive can also cause this error.
Following are the four simple solutions to help you fix this error loading operating system issue.
Solution 1: Update the system BIOS
Before starting with the process of system BIOS, it is recommended to take a backup of your data. This is because of an issue like sudden power loss which may corrupt your BIOS firmware which will not allow you to access your data. Follow these steps to update your system BIOS:
- Find the model of your motherboard from the manual.
- Get to know the version of your current BIOS by opening System Information app and select System Summary to know your BIOS version.
- If your current version of BIOS is not up to date, download the latest version of the BIOS from manufacturer’s website of motherboard or laptop. You can search for the update using the model of your laptop or motherboard.
- After downloading, install the update and restart your computer.
Solution 2: Restoring the Master Boot Record of Hard Drive
A Windows setup CD/DVD is required to restore the Master Boot Record of Hard Drive. Follow these steps to restore the MBR of the hard drive.
- Use the Windows setup CD/DVD and boot your computer.
- Upon seeing a message saying Press any key to boot from CD or DVD, press any key.
- Click on Repair your Computer and select Troubleshoot.
Select Command Prompt and enter the following four commands one by one.
- After successfully completing the process, remove the Windows Setup CD/DVD.
- Type EXIT to close the Command Prompt window and restart your computer.
Solution 3: Using Windows CHKDSK
Sometimes, a damaged hard drive can be a reason behind this error. Using Windows CHKDSK, you scan and fix a volume or a drive on your hard drive. Following are the steps to use Windows CHKDSK:
- Select Properties by right-clicking on the drive that needs to be checked for error.
- Go to Tools, click on Check under the Error-checking
- Click on Scan drive to start scanning. The scan will fix the errors and will tell you if there is any physical damage to the hard drive.
Solution 4: Reinstall the operating system
If you have tried all the above solutions and still see the same error, then you should consider reinstalling your Windows operating system.
Reinstallation of the operating system will result in deletion of everything from the system. Taking a backup before starting with the process of reinstallation is a good measure to avoid data loss. If you don’t have a backup, you can use Remo Recover software to recover files after reinstalling Windows 10.