Hey everyone, A friend of mine was trying to install a .pkg file and somehow The Unarchiver became the default app to use. I told him to uninstall The Unarchiver and tried to locate installer.app so I could set that as the default, however I was unable to locate it in Mac HD/System/Library/Core Services. I am running Yosemite but he is running Mountain Lion and I assume that's where it should be located. So, as a test, I copied my installer.app and told him to place it in that folder. The .pkg file was then recognized by Installer, however could not be opened (see pic below) I'm assuming it crashed because the Yosemite version won't run properly on Mountain Lion (maybe someone can confirm this). If that's the case: 1) Can anyone tell me the version that runs on ML (maybe someone can check what version they have)? 2) since I'm not running ML, will the installer.app from Lion work (I have a friend running Lion on his Mac)? 3) I noticed that "system" has permissions to use Installer. Do I have to set the same permission? If so, how do I do that (can't add system via gui)? As a side note, I told him long ago that he needs to get an HD to use as a Time Machine backup but he hasn't gotten around to it. I think this situation will now motivate him to do so. Many thanks in advance for any help/info anyone can provide.