It says that the "application contents were modified since the original installation." Well, yeah, I've added two plug-ins. But, even after removing those plug-ins temporarily and trying to run the update, I get the same message.
Try going to http://www.adobe.com/support/downloads/product.jsp?product=1&platform= Windows or equivalent for the MAC and download the update. See if you can do the update manually. The plugins should not be an issue as long as they did not modify the installation. If the download does not do the job, try a repair and then the update.
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