title: Why does an ad hoc ipa fail to install on one device, yet succeed on another with the same iOS version?
body: <p>I have a client whose iPad 2 (iOS 5.0) is able to install an ad hoc ipa, yet his iPhone (also iOS 5.0 -- same exact build) receives the following msg on his device when attempting to install with his Windows iTunes:</p>
  
  <p>"iTunes sync.  [app name] failed to install"</p>
  
  <p>I've worked with this guy for a long time testing many versions of this app and he's never had this problem.  All his devices install or none.  How can I solve this?</p>