Note Check the model of your WiFi & Bluetooth card. Intel cards should be compatible with itlwm (or AirportItlwm). If your card is from another manufacturer, please check if your card supports macOS.

You must have the following items:

• Lenovo ThinkPad T420 (Obviously 😁).
• Access to a working Windows machine with Python installed.
• A pendrive with more than 4 GB (Remember that during the preparation we will format the flash drive to create the installation media).
• an Internet connection (recommended via Ethernet).
• 1-2 hours of your time.

First of all, you will need the install media of macOS. I will use macrecovery to download and create the macOS Install media.

With macrecovery, the process is the following:

• Download OpenCorePkg as a ZIP.
• Extract the OpenCorePkg-master.zip file.
• Open cmd.exe with Administrator privileges and change the directory to OpenCorePkg-master\Utilities\macrecovery.
• Enter the following command to download macOS:

# Big Sur (11)
python macrecovery.py -b Mac-42FD25EABCABB274 -m 00000000000000000 download

# Monterey (12)
python macrecovery.py -b Mac-E43C1C25D4880AD6 -m 00000000000000000 download

# Ventura (13)
python macrecovery.py -b Mac-7BA5B2D9E42DDD94 download

• After the download succeeded, type diskpart and wait until you see DISKPART>

• Plug-in your pendrive and type list disk to see your disk id.

• Select your pendrive by typing select disk <diskid>

• Now we are gonna clean the pendrive and convert it to GPT. First, type clean and then convert gpt.

Note: If an error occurred, try to convert again by typing convert gpt.

• After the pendrive is clean and converted, we will create a new partition where we can put our files on. First, type create partition primary, then select the new partition with select partition 1 and format it format fs=fat32 quick.

• Finally, mount your pendrive by typing assign

• Now, close the Command Prompt and copy the folder com.apple.recovery.boot on the pendrive.

Now we are ready to make the USB drive bootable.

Download the EFI folder from this repo, you will find the latest files under the release tab or just download the repo as it is. Move the folder to the root of your pendrive (e.g. J:) and rename the folder to EFI.

We need a script, called GenSMBIOS, to create fake serial number, UUID and MLB numbers. This step is essential to have working iMessage, so do not skip it!

The process is the following:

• Download GenSMBIOS as a ZIP, then extract it.
• Start GenSMBIOS.bat and use option 1 to download MacSerial.
• Choose option 2, to select the path of the config.plist file. It will be located in EFI -> OC folder.
• Choose option 3, and enter MacBookPro8,1 as the machine type.
• Press Q to quit. Your config now should contain the requied serials.

After adding serials to your config.plist, you have to add the computer's MAC address to the config.plist file. This step is also essential to have a working iMessage, so do not skip it. We need a Plist editior, to write the MAC address into the config.plist file. I used ProperTree, since it works on Windows too. You have to change the MAC address value in the config.plist at

PlatformInfo -> Generic -> ROM

Delete the generic 112233445566 value, and enter your MAC address into the field, without any colons. Save the Plist file, and it is now ready to be written out to the EFI partition of your install media.

The default keyboard layout and language is German. To change the language, edit the value of NVRAM -> Add -> 7C436110-AB2A-4BBB-A880-FE41995C9F82 -> prev-lang:kbd to the value of your language. If your value contains an underscore "_", replace it with a hyphen "-". The value for English would be en-US:0. You can find a list of all language values here.

Please enable / disable the following patches depending on what is installed in your device.

After you've finished with the neccesary tweaks, you have to copy the EFI folder to the EFI partition of your pendrive.

The bios must be properly configured prior to installing macOS. In Security menu, set the following settings:

• Security > Security Chip: must be Disabled
• Memory Protection > Execution Prevention: must be Enabled
• Virtualization > Intel Virtualization Technology: must be Enabled
• Virtualization > Intel VT-d Feature: must be Enabled
• Anti-Theft > Computrace -> Current Setting: must be Disabled
• Secure Boot > Secure Boot: must be Disabled
• Intel SGX -> Intel SGX Control: must be Disabled
• Device Guard: must be Disabled

In Startup menu, set the following options:

• UEFI/Legacy Boot: UEFI Only
• CSM Support: No

In Thunderbolt menu, set the following options:

• Thunderbolt BIOS Assist Mode: UEFI Only
• Wake by Thunderbolt(TM) 3: No
• Security Level: No
• Support in Pre Boot Environment > Thunderbolt(TM) device: No

Now you can go through the install.

1. Boot from USB, press SPACE and select the USB drive inside of OpenCore "NO NAME (DMG)" or similar.

Note: The first boot may take up to 20 minutes.

2. Wait for the macOS Utilities screen.
3. Select Disk Utility, select your disk and click erase. Give a name and choose APFS with GUID Partition Map.
4. After erasing, go back and select Reinstall macOS and follow the steps on your screen. The installation make take up to 2 hours.

Note: Your PC will restart multiple times. Just boot from USB and select your disk inside of OpenCore. (named macOS Installer or the disk name).

5. Once you see the Region selection screen, you are good to proceed.
6. Create your user accound and everything else.

If you plan to upgrade your macOS (or updating the EFI / switching to HeliPort), you'll need a different OpenCore configuation (EFI). Please follow these steps:

Note: Download the desired macOS version in the Settings before following these steps, if you are connected via WiFi.

1. Download the newest release & ProperTree and extract it.
2. Start ProperTree and load the Config.plist on your EFI partition. (File -> Open)

Note: You can mount your EFI partition by pressing ALT + SPACE, typing Terminal and enter the following command: sudo diskutil mountDisk disk0s1.

3. Now also load the new configuration file from the repo for the desired macOS installation (or HeliPort config).
4. You should now have 2 ProperTree-windows open on your screen.
5. Go in both windows to Root -> PlatformInfo -> Generic. Transfer MLB, ROM, SystemProductName, SystemSerialNumber and SystemUUID to the new config.
6. Save the new config (File -> Save) and close both windows.
7. Now delete your existing EFI folder from the EFI partition and copy the new one to it. (Make sure that the Directorys Boot and OC are in EFI).

If you want to upgrade macOS, download the desired macOS version in the Settings app and perform the upgrade like on a real Mac.

1. Press ALT + SPACE and open terminal. Type sudo diskutil mountDisk disk0s1 (where disk0s1 corresponds to the EFI partition of the main disk)
2. Open Finder and copy the EFI folder of your USB device to the main disk's EFI partition.
3. Unplug the USB device and reboot your laptop. Now you can boot macOS without your USB device.

In case of reinstalling macOS, a offline install media can save some time. You also don't need an Ethernet connection for the installation. To create a offline install media, you need the following stuff:

• macOS Installer from the App Store.
• A 16 GB pendrive (Keep in mind, during the preperation we will format the disk to create the install media).

Press ALT + SPACE and open Disk utility. Select your USB device and click erase. Name it MyUSB and choose Mac OS Extended with GUID Partition Map. After erasing the USB device, close Disk utility.

Now press ALT + SPACE and open terminal. Type the following command:

Big Sur: sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyUSB --downloadassets

Monterey: sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MyUSB --downloadassets

Ventura: sudo /Applications/Install\ macOS\ Ventura.app/Contents/Resources/createinstallmedia --volume /Volumes/MyUSB --downloadassets

After creating the install media, copy your EFI folder to the EFI partition of your USB device.

• It boots

• Safari DRM Use Chromium powered Browser or Firefox to watch Amazon Prime Video, Netflix, Disney+ and others
• AirDrop & Continuity (devices with Intel WiFi)
• Fingerprint Reader (Disabled with NoTouchID kext)
• Sidecar Wireless
• Apple Watch Unlock
• Dualbooting Windows / Linux (with OpenCore) Theoretically, this works, but due to the ACPI patches, the respective operating system can become unstable.

• Intel WiFi & Bluetooth (thanks to itlwn)
• Brightness / Volume Control
• Battery Information
• Audio (Audio Jack & Speaker)
• USB Ports & Built-in Camera
• Graphics Acceleration
• Trackpoint / Touchpad
• Power management / Sleep
• FaceTime / iMessage (iServices)
• HDMI
• Automatic OS updates
• Handoff / Universal Clipboard
• Sidecar (Cable) / AirPlay to Mac
• SIP / FireVault 2
• USB-C
• WWAN