I have admin privileges set but cannot install 4.1.2.3 because I need to delete some 4.0 files. I have tried to dlete manually but SYSTEM won't let me

Using windows 8 with admin privileges, update has deleted prev version but can’t update/install new version 4.1.2.3

Take a look in the Windows task bar if the LibreOffice quickstart icon is there, right-click on it, and exit,a before retry.