I've just tried to install a very recently purchased CS6 upgrade for my CS5.1 but it immediately fails with the message "Installer Failed to Initialize". It suggests running the Adobe Support Advisor, which I've done but that cannot detect any issues. Where do I go from there?
Your next step would be to review the PDApp.log file. You can find directions on how to locate and review this file at Troubleshoot with install logs | CS5, CS5.5 - http://helpx.adobe.com/creative-suite/kb/troubleshoot-install-logs-cs5 -cs5.html#main_Analyze_the_Creative_Suite_5_PDapp_log.
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