iOS Simulator Doesn't Launch on Build. OSX Lion or Xcode 4.1?

Question

By Doesn't Launch I mean the icon shows up, but its hidden and if I show the windows I can see the iPhone outline but its blank inside.

I can relaunch the simulatore (Out of xcode) and it runs and I see the icons.

When I use Xcode I see: Build Succeeded. Running project on iPhone Simulator, but it never sends it over to the simulator.

Background: OSX Lion, Xcode 4.1 (from App Store), Error happens on any project.

Answer 1

I solved this by reinstalling Xcode. First I ran this command:

sudo /Developer/Library/uninstall-devtools –mode=all

Then I deleted the Developer Folder and Reinstalled Xcode. I lost older SDK's but Xcode 4.1 doesn't appear to support them for the simulator anyway.

Answer 2

I solved this by deleting the files:

~/Library/Preferences/com.apple.iphonesimulator.plist
~/Library/Preferences/com.apple.iphonesimulator.plist.lockfile

than I relaunch iPhone simulator.