Thinkpad USB keyboard - mouse buttons not working

[jlamarca1]

I have a Thinkpad USB keyboard connected to a Thinkpad T400 running XP.

The lower mouse buttons on the USB keyboard (model sk-8835) are not working. The upper buttons, touchpad and touchstick all work and everything on the laptop works. Scrolling is not working on the USB keyboard touchpad either but I don't really care about that.

I tried installing drivers for USB Ultranav and for synaptics and this hasn't fixed the problem.

Any help would be greatly appreciated!