I am running OS X Yosemite, Version 10.10.5 on my MacBook Pro.
When I tried to install the Flash Player updates, I would get this error message every time. It did not matter what ISP I was using or whether I was using Safari or Firefox as my browser.
So I tried uninstalling Flash Player and installing a clean copy, but I still get this message. Now, of course, I don't have access to any videos that could help me. Please help!