As I created a VS2008 Web Setup project I always had to specify the .Net Framework launch condition. I found no way to deactivate this on the UI. To work around this problem I used Orca 3.1 (which also enables support and correct handling of x64 application files). Open up your MSI file and go to Edit->Find and search for: VSDCA_VsdLaunchConditions Delete all rows that contain this word and save the MSI file. Now you should have gone rid of this annoying behavior/feature.
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