While reviewing a machine that had a malware issue I noticed that the machine had not updated in some time. I decided to bring the machine up to date but noticed that large numbers of windows updates and specifically XP Sp3 was failing. The pattern was odd in that it appeared to let a small number of patches install but not the bulk of what was required. The client uses Trend AV and I disabled the tool in the task tray before trying again. The updates all applied successfully. So don’t forget to check for anti-malware/antivirus interfering with updates. Simple fix to an annoying problem.