I am getting error 1723 when trying to install/re-install Java runtime 6 update 18. I am running Windows 7 for which there doesn't seem to be a release for Windows Installer (5.0). Any suggestions?
Have you tried installing Java as administrator? Or, are you doing it interactively via the Java update? If you're doing it through the updater, I would go and download the full install and try to install it that way and do it as administrator (right click on the installation exe and click "run as administrator").