I don't even know what to do with this message.

[savie079]

Adobe Reader could not open 'AdobeFlashPlayerInstaller_15_ltrosxd_aaa_aih-5.dmg' because it is either not a supported file type or because the file has been damaged (for example, it was sent as an email attachment and wasn't correctly decoded).

[pwillener]

That message looks like you are trying to open the Flash Player installer with Adobe Reader.

On Windows that means that your file association is corrupted.  On Mac OS I have no idea.

[jeromiec83223024]

Go to Control Panel > Privacy and Security and confirm that Allow Apps from Mac App Store and Identified Developers is selected.