Mouse Program to Assign Buttons on any Mouse

So, is there a program/software that allows you to assign anything to any mouse button(s)?Kinda like the Microsoft IntelliMouse Software but for any mouse because someone I know has a "no name" brand mouse with side buttons (7 in all).It must be easy to use, doesn't lag and works in games/everything.I told him that he can always go into the game controls settings but he says that he cannot set a secondary or alternative command control in some games.Thanks!

Depending on the brand of mouse, the manufacturer's driver program may.I know Logitech's Setpoint software for their mice can assign keystrokes to mouse buttons.

Replying to #2

And MS IntelliMouse for Microsoft mice...
...but it's a no-name brand. I think it's a rip off of a dell...

and dell rip them off from someone else.