Some time ago I downloaded and ran successfully Xcode 4.3.3 and Xcode 4.4 simultaneously. Then, troubleshooting I deleted them, wiping out all files referencing to both Xcode versions through Terminal. I then re-downloaded 4.3.3 and was able to launch and run it, however 4.4 which I re-downloaded afterwards refused to do the same resulting in an endless hang which to abort I could only resort to Force Quit. Having launched again I was greeted with a notification message suggesting me to either to restore previous windows or do not restore. Regardless of the option selected the hang renewed immediately until the next ForceQuit etc. I can't understand what went wrong this time? I haven't started any projects that could become corrupted or so as a common explanation suggested on numerous forums. I remember that since Apple's certificate expired and being on Lion I needed older versions of Xcode I changed the date to the one closer to the original release date. The first time trick worked with both version (although I can't remember how exactly I changed them) and so it did with 4.3.3 this time but not with 4.4. Also, if it might seem useful, when uninstalling I removed these binary files referencing to Xcode: /usr/bin/xcodebuild /usr/bin/xcode-select /usr/share/man/man1/xcode-select.1 /usr/share/man/man1/xcodebuild.1 /usr/share/xcode-select I removed these items because I thought it was bundled with Xcode and therefore would be re-installed again. Was I wrong? Was these built-in OS X? Acting on intuition I looked inside Xcode.app packages of both versions but could only find /usr/bin/xcodebuild. So what should I do?