Information Gift

Flash9+ActiveX=Angst

Turns out that later-model Flash Player 9 ActiveX installers "fix" the registry to prevent IE users from downgrading.

So if you are running the latest and greatest but need to test an earlier version, say the first release of Flash 9, it will install but won't run. Starting with r45 the installer will helpfully complain and then refuse to complete.

Nice.

Preventing users from downgrading protects same from security vulnerabilities, but makes the life of a tester difficult. The fix is to run the official Flash Uninstaller from the command line while passing a special argument that tells it to delete the relevant registry settings. Simply open a command line prompt, cd to the Flash Uninstaller's directory and run the following:

uninstall_flash_player.exe /clean

Now you can confirm that your baseline r28 detection works and your interactive does what it's supposed to. Angst lifted.