I have tried to install Plex Server which during install called for Bonjour to be installed. When I accepted it tried to install Bonjour but failed. I have no idea why. I then tried to install the newest Version of I tunes because I thought it comes with Bonjour. Now Itunes fails with "the installer encountered errors before iTunes could be configured"
I have tried to clear out the %Appdata% Temp directory and searched the registry for Apple and Bonjour and couldn't find any entries. When I look at the error Log that is created by the iTunes installer it says it errored out because of Installer Error 1618 which obviously means "Another installation is already in progress. Complete that installation before proceeding with this install". Does anyone know how I could find that installer process and terminate it so I could install Bonjour or Itunes. I am out of luck of finding anything on the web.