+4Is anyone else running into an issue with Yosemite not being able to verify? I have tried to install using the instructions provided by JAMF and I have tried downloading it separately and running it. I have scrapped the download multiple times, checked our date and time which is fine.
This is the error in case you haven't seen it. 
+18I haven't had this personally but I' suspecting its trying to check the signature or running some other checksum on the installer to make sure its genuine. That would need an Internet connection of some kind.
Is it possible to try the installer while the Mac is connected to a different (unfiltered) Internet connection?
+8I can't remember the exact error but on one of my laptops I transferred the installer from my desktop and it would not install since it was downloaded on another station. I was logged into the App Store using the same account on both stations. I ended up downloading the installer locally on the laptop and it installed.
Not sure if this is a new limitation.
+4Yea. I'm completely stumped on this one. I had NO issues upgrading on my machine (13' Inch Macbook Pro w/ Retina) with the downloaded Application. However, on 2 separate Macbook Airs, they are having the same exact issue with the same error message.
@davidacland I will try that next. Thanks for the suggestion. Will update shortly.
+5I had this problem as well check for a folder at the root of you drive called /OSInstall (I think that was the name) Delete it and then try running the installer.
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