title: Visual Studio will automatically make functional changes to the following projects in order to open them
body: <p>I decompiled a EXE and now when I try to open it. I get </p>
  
  <pre><code>One-way upgrade
  Visual Studio will automatically make functional changes to the following projects in order to open them. You will not be able to open these projects in the version of Visual Studio in which they were originally created.
  </code></pre>
  
  <p>If I click okay I get ~250 errors</p>
  
  <p>I found that need to open .csproj file and delete lines with 
  ProjectMode, TargetOfficeVersion, FileUpgradeFlags, UpgradeBackupLocation or OldToolsVersion. But I don't have in .csproj any lines like this.</p>
  
  <p>Is there a way to fix this. Or at least a way to find what Version of Visual Studio was using the author ?</p>