Edit: Attachments removed
Side note to "X": Hyperlink to WindowsXP-KB2778344-x86-ENU.exe (Feb changelog) on your XP Post SP3 High-Priority Updates page actually links to KB2779030, the superseded update it replaces.
Edit to add: Found my answer...maybe This MSFN thread led me to this thread @RyanVM forum:
2nd edit: Unchecking (keeping) Application Compatibility patch resolves the issue. I hope this info is useful to anyone who may encounter the same problem & stumble across this post.
5eraph Posted: Fri May 07, 2010 6:09 am : Make certain you are not using nLite to remove anything related to Application Compatibility. The necessary files for KB955759 are aclayers.dll and sysmain.sdb.
Edited by PinkFreud, 05 March 2013 - 09:12 PM.