How to Add a Second Windows OS to the Boot Menu

If you already have one version of Windows installed but need to add another OS to your boot menu — for example, to install a new version of Windows or to use a different build — this can be done relatively easily. In this guide, we'll go over how to add a second Windows OS to your computer's boot menu using built-in tools and a few straightforward steps.

Step 1: Install the Second Windows on a Separate Partition

Before configuring the boot menu, ensure your second Windows is installed on a different drive or partition. If it’s not installed yet, follow these steps:

  • Download the ISO image of the Windows version you need and create a bootable USB or DVD.
  • Restart your computer and boot from this installation media. Select the separate partition or drive for the new Windows installation.

Important! Do not install the second Windows on the same partition as your current system, as this can cause conflicts.

Step 2: Configure the Boot Menu with BCDedit

Once the second OS is installed, add it to the boot menu using the BCDedit tool built into Windows:

  1. Open Command Prompt as Administrator by pressing Win + X and selecting Command Prompt (Admin) or PowerShell (Admin).
  2. In the command prompt, run bcdedit /enum to view the current boot configuration and see a list of available OS options.
  3. To add a new entry in the boot menu, type: bcdedit /copy {current} /d "Second Windows Name".
  4. This command will create a copy of your current entry with the new name (e.g., Windows 10 or Windows 11).

Step 3: Configure Boot Options

Now that the second Windows option is in the boot menu, you can adjust its settings:

  1. In Command Prompt, type bcdedit /default {GUID_of_Second_Windows}, where GUID is the identifier from the previous step for your new entry.
  2. To set the selection time for choosing the OS during startup, use: bcdedit /timeout 10 (where 10 is the number of seconds for OS selection).

Step 4: Restart and Select Your OS

Once you’ve completed the commands, restart your computer. You should now see both Windows versions listed in the boot menu and be able to select either OS during startup.