Xcode 4.2 crashing on launch

I just joined developer program, downloaded Xcode 4.2 for Snow Leopard 10.6.8.

Upon the first launch it's crashing with this error:

Xcode encountered an internal logic error. Choose "Continue" to continue running Xcode in an inconsistent state. Choose "Crash" to halt Xcode and file a bug with Crash Reporter. Choosing "Crash" will result in the loss of all unsaved data.

Details

UNCAUGHT EXCEPTION (NSInternalInconsistencyException): Couldn't load plug-in 'com.apple.dt.IDE.IDEiPhoneSupport' while firing fault for extension 'Xcode.Device.iPhoneSimulator'
UserInfo: {
    NSUnderlyingError = "Error Domain=DVTPlugInErrorDomain Code=2 UserInfo=0x200819720 \"Loading a plug-in failed.\" Underlying Error=(Error Domain=NSCocoaErrorDomain Code=3587 UserInfo=0x200924300 \"The bundle \U201cIDEiPhoneSupport\U201d couldn\U2019t be loaded because it is damaged or missing necessary resources.\" (dlopen_preflight(/Developer/Platforms/iPhoneOS.platform/Developer/Library/Xcode/PrivatePlugIns/IDEiPhoneSupport.ideplugin/Contents/MacOS/IDEiPhoneSupport): Library not loaded: /System/Library/PrivateFrameworks/DeviceLink.framework/Versions/A/DeviceLink\n  Referenced from: /Developer/Platforms/iPhoneOS.platform/Developer/Library/Xcode/PrivatePlugIns/IDEiPhoneSupport.ideplugin/Contents/MacOS/IDEiPhoneSupport\n  Reason: image not found))";
}
Hints: None
Backtrace:
  0  0x00007fff87a1e766 __exceptionPreprocess (in CoreFoundation)
  1  0x00007fff87d35f03 objc_exception_throw (in libobjc.A.dylib)
  2  0x000000010001bdf0 -[DVTExtension _fireExtensionFault] (in DVTFoundation)
  3  0x0000000100006096 __38-[DVTDispatchLock performLockedBlock:]_block_invoke_0 (in DVTFoundation)
  4  0x00007fff87589fbb dispatch_barrier_sync_f (in libSystem.B.dylib)
  5  0x000000010000603f -[DVTDispatchLock performLockedBlock:] (in DVTFoundation)
  6  0x000000010001bb8b -[DVTExtension _valueForKey:inParameterData:usingSchema:] (in DVTFoundation)
  7  0x000000010001bacf -[DVTExtension valueForKey:] (in DVTFoundation)
  8  0x000000010001b2a7 +[DVTDevice _knownDeviceLocators] (in DVTFoundation)
  9  0x000000010001ae00 -[DVTDeviceManager startLocating] (in DVTFoundation)
 10  0x0000000100568fbc IDEInitialize (in IDEFoundation)
 11  0x00000001008e4f58 -[IDEApplicationController applicationWillFinishLaunching:] (in IDEKit)
 12  0x00007fff88a32ad5 _nsnote_callback (in Foundation)
 13  0x00007fff879c5fd0 __CFXNotificationPost (in CoreFoundation)
 14  0x00007fff879b2548 _CFXNotificationPostNotification (in CoreFoundation)
 15  0x00007fff88a29a36 -[NSNotificationCenter postNotificationName:object:userInfo:] (in Foundation)
 16  0x00007fff812e7901 -[NSApplication finishLaunching] (in AppKit)
 17  0x00007fff812e7554 -[NSApplication run] (in AppKit)
 18  0x00007fff812e03b0 NSApplicationMain (in AppKit)
 19  0x0000000100000eec
 20  0x0000000000000002

I think there was Xcode installed on this Mac before but I can't see it in Applications anywhere, and I launch Xcode by just searching for it spotlight. It comes up as being in /Developer/Applications

What is going on? Has anyone seen this error before? Is there a workaround?

UPDATE:

I've clicked continue several times just to see what happens, and Xcode did start. Now I am wondering if I should just continue using this or look for a root cause of this problem. Something tells me that the underlaying issue will manifest itself in weird ways later.

UPDATE 2:

Nothing works, just hangs. going to uninstall xcode with

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

and try reinstall

Solution

The solution was:

Remove all dev tools sudo /Developer/Library/uninstall-devtools --mode=all
Restart Mac (possibly optional, but I did anyway)
Reinstall Xcode