“Xcode” is damaged and can’t be opened. You should move it to the Trash

Question

Installed XCode 6 on Mavericks. It din\'t run. Updated OS to Yosemite 10.10 : Now Xcode.app (installed through *.dmg) launch fails wit

Answer 1

I know this is an older question, but if you're like me and absolutely want to install Xcode from a DMG and not from the App Store, there is a way, inspired by this post from Will Lowe that talks about installing an un-signed application.

1. Install the DMG as usual (Double-click, Drag-n-drop)
2. Open System Preferences
3. Click on "Security & Privacy"
4. Adjust the "Allow applications downloaded from:" setting to "Anywhere"
5. Open Xcode
6. Be patient while it verifies and opens

You only need to do this the first time you open Xcode, so you can change your Security settings back to their original value after Xcode has fully launched.