I was trying to run a Java applet (downloaded) through the jnlp file which came with it. And I see this error always.
I looked into the code signing certificate, and its signed from a trusted CA, and the expiry is not until 2020.
So, I narrowed down the issue to the problem mentioned in the following link: Fix the “App can’t be opened because it is from an unidentified developer” Error in Mac OS X which says that OS X has prevented any app from an external developer to not run. This change was made to Gatekeeper.
But, I was not able to find an official release doc which talks about this change.
Another place I heard that Apple has stopped the usage of Java applet all together. Did not find any official doc about that also.
Can anyone point me to a link to an official doc about these updates?
Best Answer
To open the app right-click it and click 'open'. This will open the app with Apple's Gatekeeper (System Preferences > Security & Privacy > General) still activated.
You can see more about this on Apple.com (WWDC video) and on Apple's Developer pages.
Other URLs: