At a glance

Device: Apple Magic Mouse 2024 (USB-C), called Magic Mouse v3 in this project. Bluetooth VID 05AC, PID 0x0323.
Package to install: v2-kmdf-driver — a KMDF filter driver. Installer: Install-KMDF.cmd.
OS support: Windows 10 build 14393 or later, and Windows 11 any build. x64 only.
Signing: Self-signed, so Test Mode is required. EV certificate plus Microsoft attestation signing is the goal.
Price and licence: Free, no subscription. MIT licence.
What it fixes: Two-finger scroll dying after a Bluetooth idle disconnect collapses the HID collections.

What do I need before I install?

Windows 10 build 14393 or later, or Windows 11, x64.
An administrator account — this is a kernel-mode driver.
The mouse paired over Bluetooth and reporting PID_0323.
Secure Boot off, otherwise Windows ignores the Test Mode setting.
Two reboots — one to enter Test Mode, one after the driver installs.

Install steps

Confirm your mouse reports PID 0323. Open Device Manager → Human Interface Devices → Apple Magic Mouse → Properties → Details → Hardware Ids, and look for PID_0323. If you see PID_030D or PID_0269 you have a v1 or v2 mouse; stop here and read the Magic Mouse scroll fix table for v1, v2 and v3 instead.
Download the driver package from the GitHub repo. Get the v2-kmdf-driver package from the magic-mouse-v3-windows-fix repository on GitHub. That is the recommended path and the same package the Magic Tray (Windows app) installs.
Verify the SHA256 hash of the download. In PowerShell, run Get-FileHash -Algorithm SHA256 <file> and compare the result with the hash published alongside the download. Do not install a kernel driver whose hash does not match.
Enable Windows Test Mode. The KMDF driver is self-signed today, so Windows must be willing to load test-signed kernel code. From an elevated prompt: bcdedit /set testsigning on, then reboot. Secure Boot must be off, or Windows ignores the setting. See what Test Mode actually means below.
Install the KMDF driver package. Run Install-KMDF.cmd from the v2-kmdf-driver folder as administrator. The Magic Tray (Windows app) repo ships the same action, so you can let Magic Tray do this install for you instead of running the script by hand.
Reboot and verify scroll survives a Bluetooth disconnect. Reboot. Then leave the mouse alone until Windows drops the Bluetooth link, wake it, and check two-finger scroll. That idle-then-reconnect cycle is the exact condition that used to kill the wheel, so it is the only test that matters. Background: why Magic Mouse scroll stops working on Windows 11.
Uninstall or roll back. List installed packages with pnputil /enum-drivers, find the entry for this driver, and remove it with pnputil /delete-driver <oemN.inf> /uninstall. You can also uninstall the device under Human Interface Devices in Device Manager and tick the option to delete the driver software. Then turn Test Mode off with bcdedit /set testsigning off and reboot.

What does Test Mode actually mean?

Test Mode tells Windows to load kernel drivers that are signed with a certificate Windows does not trust by default. Nothing else about the machine changes, but Windows shows a watermark in the desktop corner, Secure Boot has to stay off, and some anti-cheat and enterprise policies refuse to run while test signing is on. Turning it off is one command and a reboot.

This is a funding problem, not a design choice. Kernel drivers need an EV code-signing certificate and Microsoft attestation signing before Windows will load them normally, and that is the stated goal for this driver — see the signing and funding page.

Do not disable driver signature enforcement on a machine you do not control, and do not install kernel drivers you have not hash-checked.

Is the v1 binary patch an alternative?

No — the patched applewirelessmouse.sys in v1-binary-patch/ is research history, not the recommended path. It measured a 3.1x improvement over the unpatched baseline and it reduces, and may prevent, scroll loss, but multi-day prevention was never characterised, and it is not what the Magic Tray app installs. Use the KMDF package above.

What should I read next?

Magic Tray is Windows software — a system-tray utility — not a desk accessory, stand, or 3D-printed tray.

Magic Mouse 2024 (v3) scroll not working on Windows 11 — symptoms, cause, and the PID lookup table.
Magic Mouse battery percentage on Windows 11 — what actually reads the battery.
Magic Mouse v3 Windows driver FAQ — signing, Boot Camp, v1 and v2 support.
Magic Tray (Windows app) — installs this driver and shows battery percentage in the tray.