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The 4.2.12 Installer downlaods a file that is 217 Mb, not 208 as stated on the download page, and when installed, produces a broken installation that won't start and instructs the user to move it to 'Trash'.  Downloaded 3 times with same result.

Overwriting with the previous version (4..2.11) restores functionality.

Having the same issue and it appears to be an issue with Sierra and Gatekeeper. There is no longer an option to download apps from "anywhere" (System Preferences>Security and Privacy). The choices are App Store and App Store and identified developers.

The inability to open the download has something to do with the certificate and signature. There's a thread on GitHub regarding Spotify.

I've found a entry that can be used in Terminal, but it presents a pretty serious security risk as it disables Gatekeeper. 

Just found this:

Open Terminal and type in  xattr -rc /Applications/PlayonMac.app

Not sure if there is a security risk...kinda doubt it because this is specifically for POM...but it did allow the new version to run.

Just tried the more direct 'trick':

Hold down the CTRL Key while selecting the Installation File and then choose Open.  

This produces a functional installation of 4.2.12, as with previous versions of POM which do not need any trickery, so something has definitely changed in POM, as 4.2.10 and 4.2.11 install on MacOS (Sierra) without causing this problem.

Is the problem fixed with the current version?

Thanks for the workaroud proposals. However, they didn't work for me. The Terminal command produced a string of "Permission Denied" messages, and the right-click and open workaround produced the same result, forcing me to move the file to the Trash. 

Any other suggestions by chance? 

Edited by sbertran

I'll tell you in just a moment. Downloading it now. 

Got past the first verification, and then had to open the program from security panel in Settings. After this, it appears to work fine. 

Edited to add: Thanks for the fix! Works great. Merci bcp ! Je peux confirmer qu'il marche très bien. 

Edited by sbertran

Bonus: The version fixes printing issue and supports 64bits wine package.

Just downloaded a 'new' build of 4.2.12 which was substantially larger than the original installer (255Mb).  This installs normally, but requires CTRL + 'Open' for the first run after installation, which most experienced users will know as quite normal for 'unsigned' software.  

This 'version' also includes the ability to download and use 64-bit builds of Wine, which wasn't present in the earlier build which presumably explains the increased size of the download.

This installs normally, but requires CTRL + 'Open' for the first run after installation

Quote from Erdeslau

question, is there anywhere a changelog?

question, is there anywhere a changelog?

Just few 4.2.11 regressions fixed, 64bits wine support and wine updated to 2.0.2 basically