title: Debug and Release Build works fine but the Distribution/AdHoc Crashes
body: <p>HI there,
  Some users of my application have reported me that my application is no longer working. It closes just after launching it.</p>
  
  <p>I have been trying to identify the crash for days with no luck using builds debug and release and testing it in several devices. This morning I was surprised when I was able to reproduce the problem by generating a AdHoc version and installing it on my iPhone.</p>
  
  <p>I have already tried to remove all the custom configurations and recreate them using a copy of the release version but it did not work.</p>
  
  <p>I got this error below when I was running in the simulator and the crash reports also points to the same place...</p>
  
  <p><strong>Detected an attempt to call a symbol in system libraries that is not present on the iPhone:fwrite$UNIX2003 called from function -[My7zipExtract extract7zFile:]</strong></p>
  
  <p>So, my question is: What is the difference between build Debug/Release and Distribution (App Store/Ad Hoc). I have double checked everything and the only difference are the certificates.</p>
  
  <p>Any help is appreciated.</p>
  
  <p>Many thanks</p>