If you are using a mouse with more than three buttons and a wheel on a Linux system, you probably heard about using evdev instead of the default mouse driver. Unfortunately, many of those tutorials on the net contain mistakes due to old parameters or manly by simply mixing up evdev and mouse options. However, it is quite easy to set it up.

If you want to use evdev just add (keep your Configured Mouse block) these lines to your xorg.conf

And this line into ServerLayout:

Just make sure you replace the device with the path to your mouse.
Otherwise you can run

to get the right device. That’s it! Your done.

Step 2 for Laptop users
If you are running Linux on a Laptop you might have a InputDevice called something like Synaptics Touchpad. If that is the case, go ahead and remove your Configured Mouse InputDevie block and remove the “Option SendCoreEvents true” line in your Touchpad Device.
Now add Corepointer behind the Touchpad InputDevice in the ServerLayout like here:

It is important that the Touchpad becomes CorePointer even though you use an external mouse the whole time, because otherwise your X-System will not boot if your mouse is not connected.

Now your are all set and can use all your mouse buttons. Use xev and xbindkeys to map you new buttons to other functions.