How to Sync a Wireless HP Mouse to a Computer
Before you can use an HP wireless computer mouse, it must be "synced" to your computer. The term "synced," in this specific context, means that the computer and the mouse can communicate with one another and your motions with the mouse will be reflected on-screen. Accomplish this using wireless technology, similar to the type used to transmit wireless Internet signals, and a USB connectivity device called a "dongle."
Insert the USB dongle that came with your HP wireless mouse into a USB computer port on your machine. This dongle, which resembles a regular flash drive in appearance, can be plugged into any available USB port. Once inserted, it immediately turns on.
Insert the required amount of batteries (typically two AA batteries, though it changes depending on the model) into the compartment on the bottom of your HP wireless mouse.
Flip the "ON" switch on the bottom of your HP wireless mouse.
Press the "Sync" button on the bottom of your HP wireless mouse. The mouse will now sync with your computer and will be immediately usable.