My laptop cursor seems to be going haywire.Has anyone any ideas how to help?

Sometimes things work fine but at others the words come out semi-scrambled, very difficult when working on long bits of prose. I occasionally get a message telling me that there is a problem with the alps pointing device and that I should go to the maker's website and download an upgrade. However, Hewlett Packard do not seem to have such an upgrade available. Any advice on what to do next would be gratefully received.