well... can you give us more info.
Go to control panel-
Click "Switch To Classic View" Its on the left side of screen
Select Administrative Tools
Select Computer Management
Select Device Manager
Expand "Mice and other pointing devices"
What do you see?
Also, it probably needs software to be installed so i would suggest installing the software included with the mouse. (if their is any, i dont know i have the MX)
Next time, please just give us a little more info, so we dont have to do ALL the work