If it's connected via a KVM switch, connect the mouse directly to the
machine (for setup only). At KVMs with repeater machine are unable to
detect the mouse itself.
I have a generic 3-button mouse which claims to be MS mouse
compatible. However, I'm unable to get XF86 to recognize the middle
I've tried the MS protocol (which works except for the middle button),
and the MouseSystems protocol (which doesn't work at all). I've tried
all the options I could find, too.