Mac Developer Tips » How to Uninstall Xcode
I hate, that I have to restart this computer.
Even after this the app store still thinks XCode is installed and up-to-date.
What a mess!
I had to remove “/Applications//Install Xcode.app”, only after this, I could re-install Xcode.
Mounting xcode_4.1_for_lion.dmg and executing the pkg file in there did not yet re-install Xcode, only executing “/Applications/Install Xcode.app” did.
Maybe executing the later would have re-installed it properly in the first place …