When I started programming with Cocoa-Touch a guy who teached me Objective-C's basis said «Everybody loves Cocoa. Not much people loves XCode».
Forgetting some boring and stressful troubles (mainly about memory management), I agree with him, because last "iPhone SDK Troubles" came from XCode. It gives me this error:
Error from debugger: Error launching remote program: security policy error
It taken me a lot to resolve it, because it seemed an error related to Info.plist or a bad-configured provisioning profile.
Instead it was easy: just delete all expired provisioning profiles from your device (iPhone/iPad). Go to Configuration->General->Profiles and delete them.
I was tired, so I deleted all profiles and I rebooted the device, but after I was able to install applications from XCode to iPad.