Xcode 6.1.1 not launching: Loading a plugin failed

I updated Xcode from latest 5.* version to 6.1.1 via App Store but every time I try to launch it it gives me the error message: "Loading a plugin failed - The plugin or one of its prerequisite plugins may be missing or damaged and may need to be reinstalled".

I'm running Mac OS X Version 10.9.5 (Mavericks).

I tried to:

- Delete Xcode by deleting it from my Application folder and install it again from App Store.

- Download and install Xcode from Downloads for Apple Developer.

- I tried launching from different user account (guest to be precise).

Nothing worked!

I want to view the crash log or more detailed report about the issue, where can I find something like that?

Can anyone help to work this problem, I would try and downgrade back to Xcode 5 but need iOS 8 SDK so that's not going to help.

Thank you.