EnableWheelDetection

HKLM\SYSTEM\CurrentControlSet\Services\i8042prt\Parameters

Data type	Range	Default value
REG_DWORD	0 | 1 | 2	1

Description

Determines whether the driver attempts to detect and enable the wheel on the mouse device. Some devices are equipped with a mouse wheel to provide rapid scrolling and other control features if supported by an application.

Value	Meaning
0	Disable mouse wheel detection. The driver does not attempt to determine whether the mouse has a wheel or to enable it. Even if the mouse has a wheel, the wheel does not function in programs.
1	Detect and enable the mouse wheel. If the driver detects a wheel on the mouse, it enables the wheel.
2	Enable without detecting. The driver attempts to enable a mouse wheel without determining whether the mouse has a wheel.

Note

This entry is used only when a device is installed. When the system recognizes a new device, it copies this entry to a device-specific subkey in the Enum subkey. Thereafter, it uses only the entries in Enum.

For mouse devices that do not fully support all Intellimouse and PS/2 functions, including dynamic enabling, set the value of this entry to 2.

Tip

To view or change the value of this entry for a particular PS/2 mouse, use Device Manager. In the tree control, click Device and then, in the results pane, click Mouse, double-click the device name, and click the Advanced Settings tab. This value appears in the Wheel Detection box.

Caution

In rare instances, when the system tries to detect and enable the mouse wheel, the system stops responding. To recover, restart Windows 2000. If the problem persists, restart by using the LastKnownGood control set .