![how to repair an imac operating system how to repair an imac operating system](https://iboysoft.com/images/resource/macos-big-sur-problem.png)
Step 4: Now restart your computer again by placing operating system installation CD on CD / DVD drive Follow the on-screen commands to save your new settings and exit BIOS setup.
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On consequential screen, choose CDROM / DVD option, and then press the ESC key until you get back to the main BIOS screen. Then you have to select Advanced Options or another submenu to find it. Press arrow keys to select this option and press Enter. Step 3: Select an option called First Boot Device Keep in mind that you have only a few seconds to press this key to suspend the booting process and enter the BIOS screen. In this step, you need to press the F2 key before booting process startups to get BIOS- Basic Input Output System settings. Step 2: Restart your computer and watch the screen carefully So, keep a copy of personal files to avoid such circumstances. It is a best practice before performing any changes to your PC because we cannot tell how your data may get lost. Step 1: Take a backup of all the personal files on your computer
#How to repair an imac operating system how to
In case you do not know how to reinstall OS without losing data, then follow below-mentioned guidelines and make your system’s performance best by retaining stored files.
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Therefore, the user wants to re-install the existing OS without losing existing data and makes the system to work efficiently. Due to this issue, the system’s performance becomes very slow, and the application will delay opening. Virus and malware attacks are one of the major reasons behind corruption of Windows Operating System.