preflight file error
Has anyone else come across an error while using the Mac App Store where you cannot get an app to update, or download, because of a "preflight file error", where the app says that it's not signed by Apple.
This started for me after I started using Yosemite, and I have two-factor authentication activated. Usually I can work around the error and get the app to update, or download bu using Update All, but I'm trying to download the El Capitan public beta now, and the program will not download.
Mac mini, OS X Yosemite (10.10.4), Mac App StoreHas any o