Couldn't register with the bootstrap Server
I was able to recover from this by unplugging the iPad, powering it down and back up, clearing all XCode caches and targets, and doing a clean build.I'm running XCode 3.5.4 and iOS 4.2.1Hope this helps someone.-Mike
UPDATE: Same problem running Xcode 4.3 and iOS5 - just power-cycle the device.
You might wish to kill all Simulator processes, that can cause this error as well.
Here's a one-liner to kill 'em all:
kill -9 `ps ax | grep Simulator | grep -v grep | awk '{print $1}'` Or more concise, like @brianegge mentions as a comment:
killall -9 Simulator