title: Upgrading from Visual Studio 2008 to 2015 - what worries should I have?
body: <p>I have just taken over ownership of some apps in a new job - mainly consisting of C# &amp; ASP.Net web projects, targeting .Net Framework 3.5.</p>
  
  <p>Currently the company uses VS 2008 for the solutions, I'd like to look at upgrading to 2015.</p>
  
  <p>Can I easily do this without making any breaking changes to the compiled code?  What problems might I expect to come across?
  And if all goes ok, how can I be sure that the new compiled code is identical to the old?</p>