I don't know if you have tried this or not, but it is always a good idea to disable non windows services from within msconfig when running a windows update. In msconfig, select the services tab and choose "hide all Microsoft services". Then "disable all", reboot, and try your update again. If it goes through, don't forget to go back into msconfig and enable the services again.
No I have not tried that. I have disabled my security and external hard
drive, but that made no difference. I am away from home now for 3 weeks, so
will give that ago when I return. Thanks for the tip.