Altiris locking ntuser.dat on logout on Citrix systems
SMF (Software Management Framework) Agent tries to monitor Citrix's entry HKU\'upm_S-1-5-21-3993733659-2646350369-2562511232-5233_logoff\Software\Microsoft\Windows\CurrentVersion\Uninstall' which seems to be added there on logoff.
Release: 8.6 GA/RU1
Component :SMF Agent
Known issue. A fix for this is expected to be added to the ITMS 8.6 RU2 release.
A pointfix for ITMS 8.6 RU1 is available under KB 221269 "CUMULATIVE POST ITMS 8.6 RU1 POINT FIXES"