[. . . ] Caution: To use this product properly, please read the user's guide before installation. Please adhere to the following warnings and safety instructions to prevent injury: 1. [. . . ] For PS/2 mouse port installation Please turn off your computer before installing your mouse. Plugging and unplugging cables to your computer's mouse port while the computer is running can damage the mouse port or your computer. Insert the Windows driver CD into the computer's CD-ROM drive when asked to do so. CAUTION: Change or modifications not expressly approved by the manufacturer responsible for compliance could void the user's authority to operate the equipment. How to use the wheel Your mouse has a wheel that functions both as a wheel for Windows scrolling and also as a customized button. It can be used as a standard mouse button, click (press down) the wheel. Caution: It may sometimes interfere the sensor of the mouse, if your tabletop surface is in red color, transparent as glass or highly reflective like a mirror. Try to use a mouse pad or use your mouse on a different tabletop surface. Try one or more of the following: · Make sure you have installed the mouse correctly. Refer to your computer documentation for the correct port configuration. Disclaimer Information in this document is subject to change without notice. The manufacturer does not make any representations or warranties (implied or otherwise) regarding the accuracy and completeness of this document and shall in no event be liable for any loss of profit or any commercial damage, including but not limited to special, incidental, consequential, or other damage. [. . . ] Figyelmeztetés: It may sometimes interfere the sensor of the mouse, if your tabletop surface is in red color, transparent as glass or highly reflective like a mirror. Try to use a mouse pad or use your mouse on a different tabletop surface. [. . . ]