Download Kali and Create Bootable USB
The installer needs to run from external media. The USB must be flashed in GPT mode with a UEFI-compatible bootloader, otherwise your PC won't recognize it as a bootable device.
Download the ISO
Go to the official Kali downloads page and grab the 64-bit Installer image. Don't download the "Live" version for a dual-boot install the installer version gives you a persistent installation with proper partition management. The file will be around 4GB.
Flash with Rufus
Download Rufus (free, no installation required). Insert an 8GB+ USB drive. In Rufus, select your USB, select the Kali ISO, and critically: set Partition scheme to GPT and Target system to UEFI (non-CSM). Leave everything else default and click Start. Rufus will format the drive and write the bootable image.
Alternative on Linux or Mac: Use balenaEtcher or the dd command. The key requirement is the same the USB must be GPT-partitioned with an EFI system partition, which Etcher handles automatically.
Shrink Windows Partition
Kali needs unallocated disk space to create its root, home, and swap partitions. You create this by shrinking your existing Windows partition not by deleting it or creating a new volume in Windows (which would format it as NTFS, and Kali can't use that).
Open Disk Management
Right-click the Start button and select Disk Management. You'll see your drive layout typically one large C: partition taking up the entire disk.
Shrink the volume
Right-click the C: drive, select Shrink Volume. Windows will query for available shrink space. Enter at least 40960 MB (40GB). Click Shrink. You'll see a new black bar labeled "Unallocated" appear next to C:.
Don't create a new volume here
Windows will offer to create a new simple volume from the unallocated space. Skip this. The Kali installer needs raw unallocated space if you format it as NTFS or exFAT in Windows, the installer won't be able to use it properly for Linux partitions.
How much space? 40GB is the practical minimum for Kali if you plan to install tools and store files. 60–80GB is comfortable. If you have a 256GB drive, 40GB is fine. If you have a 1TB drive, allocate more you'll thank yourself later when you're working with large datasets or VM images.
Disable Fast Startup and Configure UEFI
Two Windows features commonly break dual-boot setups. Fast Startup writes a hibernation-like file that locks the NTFS partition, preventing Linux from reading or modifying it. Secure Boot can block the Kali bootloader if it's not signed. Both need to be handled before you boot the USB.
Disable Fast Startup in Windows
Open Control Panel → Power Options → click "Choose what the power buttons do" on the left. Click the blue text "Change settings that are currently unavailable." Uncheck "Turn on fast startup (recommended)". Save changes.
Enter BIOS/UEFI
Restart your PC. During the boot logo screen, press the BIOS key repeatedly. This varies by manufacturer: F2 for Dell/ASUS, F10 for HP, Delete for most custom boards. If you miss it, hold Shift + Restart from Windows → Recovery → Advanced Startup → UEFI Firmware Settings.
Disable Secure Boot
Navigate to the Boot or Security tab. Set Secure Boot to Disabled. While Kali technically supports Secure Boot with signed shim, disabling it eliminates a whole category of boot failures on first install. You can re-enable it later after GRUB is properly configured.
Verify Boot Mode is UEFI
Still in BIOS, confirm "Boot Mode" is set to UEFI, not "Legacy" or "CSM." If you see a "CSM" (Compatibility Support Module) option, disable it. Save changes and exit. The PC will reboot.
BitLocker warning: If your Windows drive is BitLocker-encrypted, shrinking the partition may trigger a BitLocker recovery on next boot. Make sure you have your recovery key saved (usually in your Microsoft account). The shrink operation itself doesn't encrypt or decrypt anything it just resizes the partition but some BIOS changes can trigger BitLocker's tamper detection.
Boot from USB and Install Kali
With the preparation done, the actual installation is straightforward. The key decision point is the partitioning step selecting the wrong option here is how people accidentally overwrite Windows.
Boot from the USB
Insert the USB. Reboot and press the boot menu key (F12, F11, or Esc depending on your motherboard). Select the USB drive from the list. You'll see the Kali boot menu select the first option (Graphical Install).
Walk through the installer prompts
Select your language, location, and keyboard layout. When you reach the network configuration step, connect to Wi-Fi or plug in Ethernet the installer needs network access to fetch package lists and install software.
Partitioning the critical step
When you reach "Partition disks," select "Guided use the largest continuous free space." This is the option that targets only the unallocated space you created. Do NOT select "Guided use entire disk" that will wipe Windows. The installer will automatically create / (root), /home, and swap partitions within the free space.
Finish the installation
Set your username and password. Select "Install the GRUB boot loader to the master boot record" it should default to your primary drive (e.g., /dev/nvme0n1), not a partition like /dev/nvme0n1p1. Complete the install. When prompted, remove the USB and reboot.
GRUB target matters: If GRUB installs to a partition instead of the drive, Windows Boot Manager won't chainload it and you'll boot straight to Windows with no GRUB menu. If this happens, you'll need to boot from the Kali Live USB and reinstall GRUB using grub-install /dev/nvme0n1 from a chroot environment.
Post-Installation Verification
After the first boot into Kali, a few things need checking before you start using it for real work.
Verify the GRUB menu appears
Reboot the PC. You should see the GRUB menu with both Kali Linux and Windows Boot Manager listed. Select Windows to confirm it still boots. If GRUB doesn't appear, see the FAQ section below.
Update Kali immediately
Open a terminal and run sudo apt update && sudo apt full-upgrade -y. The ISO you downloaded may be weeks old, and Kali's tools update frequently. Running this before you start working ensures you have current package versions and security patches.
Verify Windows is accessible from Kali
Kali should auto-mount your Windows partition under /mnt/windows or a similar path. Open your file manager and check. If it's not mounted, you can mount it manually with sudo mount -t ntfs-3g /dev/nvme0n1p3 /mnt/windows (adjust the partition number to match your Windows partition).
Frequently Asked Questions
This means GRUB either wasn't installed correctly or Windows Boot Manager overwrote the EFI boot entry. First, enter BIOS and check if a "kali" or "ubuntu" boot entry exists in the boot order if it does, move it above Windows Boot Manager. If no Linux entry exists, boot from your Kali USB in live mode, open a terminal, and run sudo grub-install /dev/nvme0n1 (replace with your drive). If that still doesn't work, use boot-repair from a live session.
Use GPT. MBR is a legacy standard limited to 4 primary partitions and 2TB drives. Windows 11 requires GPT anyway. If your drive is somehow still MBR (rare for a Windows 11 machine), you'd need to convert it which requires backing up all data, wiping the drive, and reinstalling Windows. Check your partition table in Disk Management by right-clicking the disk (not the partition) and looking at "Partition Style."
Not if you select "Guided - use the largest continuous free space" during partitioning. This targets only the unallocated area. However, partition operations carry inherent risk a power outage mid-shrink or a mis-click in the partitioner can cause data loss. Back up important files to an external drive before starting. It's not paranoia; it's standard practice for any disk modification.
Yes. Kali includes ntfs-3g, which provides read/write access to NTFS partitions. Your Windows drive typically mounts automatically under /mnt/windows. If it doesn't, you can mount it manually. Be careful not to modify system files on the Windows partition from Linux — Windows may mark the drive as dirty and run a chkdsk on next boot, which is normal but can be alarming if you're not expecting it.
Installation Failed?
Getting a cryptic error, black screen, or missing GRUB menu? Post your error and we'll help you debug it.
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