I get a Windows Installer error: This package could not be opened. Contact the application vendor to verify that this is a valid Windows Installer package.
I am using this the same way I installed previous update packages such as 8.2.3.
This sounds like a corrupted download. Download it again from http://ardownload.adobe.com/pub/adobe/reader/win/8.x/8.2.4/misc/AdbeRdrUpd824_all_incr.msp
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