Due to some problems with the upgrade for the 3.0 .Net framework (which many of the lab machines had), XP Service Pack 3 was not able to install. The workaround was to manually install the 3.5 framework, which included all the updates to the previous versions of .Net framework. I was having a little trouble install it using psexec, but that was caused by the framework executable displaying an Open File Security Warning when it ran. By right-mouse clicking on the file and selecting “Properties” I was able to click on the “unblock” button and remove the dialog. The remaining machines were then able to apply the framework, and after SP3. The one holdout had a problem with RAM which was causing windows update and other services to crash. Removing the ram looks like it has resolved the problem.