Wireless mouse and keyboard

[silverback]

Sorry if this is a question, but I can't find a definitive answer.

When I bought my Lenovo PC, it came packaged with a wireless keyboard and mouse as a set. This had only one wireless dongle to plug into the PC. Therefore, the mouse and keyboard must be on the same frequency.
The mouse has now given up.
Is there any chance that a new Lenovo mouse can use the existing dongle or will it need to take up another USB slot i.e. I'll end up with two USB slots occupied?
The keyboard is still going strong, so I don't want to purchase a new keyboard/mouse set.
Silverback

[HansV]

You should be able to pair the dongle with a new Lenovo mouse. Press the pairing button on the mouse for at least one second; it should automatically connect to the USB receiver.

[silverback]

Apologies. Pairing button? I have no idea what this means. I can't find anything which could be this on my existing Lenovo mouse - and I'm thinking of getting the same model again.
Silverback

[HansV]

If you turn over the mouse, it should be the button on the left side of the bottom of the mouse.