A technician adds a second SATA hard drive to a Windows 10 desktop so the user can store large project files. After the installation, the PC powers on, POST completes successfully, but the screen now shows the message "Operating system not found" and immediately reboots. Both drives are visible in the firmware setup utility. Which of the following should the technician check FIRST to restore normal operation?
The SATA data cable connection on the newly installed drive
The SMART health status of the original system drive
The drive order defined in the UEFI/BIOS boot sequence
Whether the system partition is marked Active in Disk Management
Because the system worked before the extra drive was added, the most likely cause is that the firmware is now attempting to start from the blank drive instead of the original system disk. Verifying and correcting the boot order in UEFI/BIOS is a quick, non-destructive first step. Reseating the new drive's cable or examining SMART data could help if hardware problems are suspected, and marking the system partition active is usually attempted later from a recovery environment-after confirming the correct disk is selected-rather than as the initial action.
Ask Bash
Bash is our AI bot, trained to help you pass your exam. AI Generated Content may display inaccurate information, always double-check anything important.
Why would adding a second drive cause the 'Operating system not found' error?
Open an interactive chat with Bash
What is UEFI/BIOS and how does the boot order work?
Open an interactive chat with Bash
What happens if the system partition isn't marked as Active?