Booting Windows 10 and Ubuntu Together Without GRUB

Many users wish to run both Windows 10 and Ubuntu on the same machine without using GRUB as the bootloader. While GRUB is the default bootloader for Ubuntu, there are alternative methods that allow these two operating systems to coexist peacefully, booting Windows 10 by default. This guide will explore these methods and offer detailed steps to follow for a seamless experience.

Using a Live USB

If you frequently need to switch between Windows 10 and Ubuntu, one efficient approach is to create a live USB of Ubuntu. By booting from this live USB, you can run Ubuntu without disturbing the bootloader of your Windows installation. Here are the steps:

Steps to Create and Use a Live USB

Create a Live USB: Use a tool like Rufus (for Windows) or UNetbootin (for Linux) to create a bootable USB drive with Ubuntu.

Boot from Live USB: When you want to use Ubuntu, restart your machine and set the boot device to your USB drive. This can typically be done by pressing a key during boot (e.g., F12 or F2) and selecting your USB drive from the boot menu.

Use Ubuntu: Once booted from the USB, you can work on Ubuntu without affecting your Windows installation. Remember to unplug the USB drive when you're done.

Disconnect USB: When you’re finished, plug the USB back in and restart your machine to boot into Windows 10.

While this method is extremely flexible, it requires the USB to be connected every time you want to use Ubuntu, which can be inconvenient.

Using a Boot Manager

For a more permanent solution, you can use third-party boot managers like EasyBCD or rEFInd to choose between Windows and Ubuntu. These tools provide a graphical interface for configuring your boot options and can coexist with your Windows bootloader.

Steps to Set Up EasyBCD

Install EasyBCD: Download and install EasyBCD. Launch the application and follow the prompts to get started.

Add a New Entry: In the Main Menu, select Add New Entry and choose Windows 2000/XP/NT/2003/ Vista/7/8/10 to add a new Windows entry. Select the drive where Windows is installed as the system drive.

Configure Boot Options: Go to the Boot Options page and configure the timeout as desired. You can set it to boot into Windows by default, with an option to select Ubuntu when needed.

Save Changes and Reboot: Click Save Settings, then reboot your machine to see the new boot menu. From now on, you can boot into Windows or Ubuntu using the EasyBCD menu.

Other Boot Managers

Another advanced boot manager is rEFInd. rEFInd can automatically detect installed operating systems and provide a menu to choose between them at startup. It is particularly useful in UEFI environments.

Download and Install rEFInd: Download the appropriate version of rEFInd from the official website. Follow the installation instructions provided for your operating system.

Configure rEFInd: Once installed, edit the file to adjust the boot options. You can specify default boot entries and customize the boot menu as needed.

Important Notes

Before making any changes to your boot settings or partitions, ensure you have backed up all important data. Additionally, make sure both operating systems are installed in the same mode (UEFI or Legacy) to avoid boot issues.

Note that running Ubuntu from a live USB can be slower than a full installation, especially if you frequently switch between the two operating systems. Consider a full installation for a smoother user experience.

Alternative Approach: Deleting Ubuntu Partitions and Repairing Windows

If you primarily use Windows 10 and only occasionally need to boot into Ubuntu, you might want to simplify your setup by deleting the Ubuntu partitions. This will free up unused space and prevent errors that can occur when both operating systems are present.

Steps to Repair Windows

Create a Windows Repair Disk: Use a tool like Windows ADK (Automated Deployment Kit) to create a bootable repair disk.

Boot from Repair Disk: Restart your machine and boot from the repair disk. Select Repair your computer from the menu.

Select Troubleshoot: In the Advanced Options, select Troubleshoot. Then, choose Startup Settings and reboot your machine, hitting F4 to enter Safe Mode.

Install Windows Bootloader: Go to the command prompt and enter the following commands to install the Windows bootloader and repair GRUB:

bootrec /fixmbr bootrec /fixboot bootrec /scanos bootrec /rebuildbcd

After repairing the Windows bootloader, reboot your machine to see the Windows boot menu. If the repair process does not restore GRUB, you may need to use a third-party tool like EasyBCD to add options for Ubuntu.

Remember, modifying your bootloader or partitions can be risky. Always proceed with caution and ensure you have backups of all important data.