title: VS 2015: How to debug Access Violation from MSVCR120.dll
body: <p>I am working on a VS 2015 MVC C# web application for a client. The application has been stable for a couple of years, but the client has asked me to integrate some C++ DLLs that perform engineering calculations relevant to our web application.</p>
  
  <p>Unfortunately there is no source code and documentation does not exist (don't ask me why...). So I am somewhat blind to how to use these DLLs.</p>
  
  <p>When I load the main DLL and attempt to use it I get the following error:</p>
  
  <pre><code>Failed to load library SQLite3Ex.dll
  </code></pre>
  
  <p>Event viewer contains this entry:</p>
  
  <pre><code>Faulting application name: iisexpress.exe, version: 10.0.10557.1000, time stamp: 0x560abee8
  Faulting module name: MSVCR120.dll, version: 12.0.21005.1, time stamp: 0x524f7ce6
  Exception code: 0xc0000005
  Fault offset: 0x0000f20c
  Faulting process id: 0x1450
  Faulting application start time: 0x01d1c6773bd1167d
  Faulting application path: C:\Program Files (x86)\IIS Express\iisexpress.exe
  Faulting module path: C:\WINDOWS\SYSTEM32\MSVCR120.dll
  Report Id: 5d46a86a-2202-4d6e-af41-8426c16966e9
  Faulting package full name: 
  Faulting package-relative application ID: 
  </code></pre>
  
  <p>I'm not sure how to troubleshoot this problem and was hoping someone could point me in the right direction. I think this is a general error - could be a missing .cfg file or even a missing DLL? But I'm not sure how to determine the problem.</p>