title: Visual Studio Error: "Object reference not set to an instance of an object" when clicking on a project and opening Properties
body: <p>I have a weird behavior of Visual Studio 2013 (and 2010), that i cant seem to fix.</p>
  
  <p>I know this is not directly related to programming (similar questions achieve the same error message via code, so i assume it is code within VisualStudio that has a problem).</p>
  
  <p>My projects are C++.</p>
  
  <p>Whenever i click on a project and open its properties, i get the following error box:</p>
  
  <p><img src="https://i.stack.imgur.com/HUZyw.png" alt="Error Message"></p>
  
  <p>with the text:</p>
  
  <blockquote>
    <p>Object reference not set to an instance of an object.</p>
  </blockquote>
  
  <p>I can trigger that error message by selecting "Configuration Properties -> General". The view then does not show the information for "General".</p>
  
  <p>My setting is the following: Windows 7 Enterprise SP1 64bit, Visual Studio 2010 (i need the compiler) and Visual Studio 2013 Professional (Update 4).</p>
  
  <p>I have to work with these extensions:</p>
  
  <ul>
  <li>IBM Clearcase Integration</li>
  <li>IBM RTC VS Integration</li>
  <li>Visual Assist X</li>
  <li>Xoreax Incredibuild</li>
  </ul>
  
  <p>What i did try without success:</p>
  
  <ul>
  <li>Remove all VS related files/folders in 
  
  <ul>
  <li><code>%APPDATA%\..\Local\Microsoft</code></li>
  <li><code>%APPDATA%\..\Roaming\Microsoft</code></li>
  <li><code>%PROGRAMFILES%</code></li>
  <li><code>%PROGRAMFILES(X86)%</code></li>
  <li><code>%USERPROFILE%\Documents</code></li>
  </ul></li>
  <li>Repair/Reinstall VS2010 and VS2013 (i always installed VS2010 first)</li>
  <li>Reinstall .NET Framework 4.5.2</li>
  <li>Create a new project from within VS2013, i get the usual error plus:<img src="https://i.stack.imgur.com/z8nP0.png" alt="new_proj_error"></li>
  <li>Use TotalUninstaller as described <a href="https://stackoverflow.com/a/28050106/875020">here</a> to remove all extensions</li>
  <li>Hooking into the devenv process with WinDBG did not work (in non-invasive i couldnt get it to run)</li>
  <li>Start devenv.exe with <a href="https://msdn.microsoft.com/en-us/library/ms241278.aspx" rel="nofollow noreferrer">safemode</a> and <a href="https://msdn.microsoft.com/en-us/library/ms241272.aspx" rel="nofollow noreferrer">log</a></li>
  <li>Uninstall NuGet as proposed <a href="https://stackoverflow.com/a/17312698/875020">here</a></li>
  <li>Create new solution and delete old .suo and .sdf files</li>
  <li>Look at output <img src="https://i.stack.imgur.com/O8PO8.png" alt="output"> of <a href="https://technet.microsoft.com/en-us/library/bb896645.aspx" rel="nofollow noreferrer">ProcMon</a> while triggering the error. I checked the registry for that key: nonexistent</li>
  <li>Look at <a href="https://gist.github.com/anonymous/2e32538548fcbf10c204" rel="nofollow noreferrer">logfile</a> at <code>%APPDATA%\..\Roaming\Microsoft\VisualStudio\12.0\ActivityLog.xml</code> generated via /log: the keys are found within other keys of the value "(Default)". No clue on how to interpret that</li>
  <li>Reset all user settings via the (also secret) options named <a href="https://stackoverflow.com/a/19460071/875020">here</a></li>
  <li>Run .NET <a href="https://support.microsoft.com/en-us/kb/2698555" rel="nofollow noreferrer">Fixing Tools</a> and <a href="https://support.microsoft.com/en-us/kb/929833" rel="nofollow noreferrer">SFC</a></li>
  <li>Clean (remove from) registry
  
  <ul>
  <li><code>HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\</code></li>
  <li><code>HKEY_LOCAL_MACHINE\Software\Microsoft\VisualStudio\</code></li>
  </ul></li>
  </ul>
  
  <p>So my questions are</p>
  
  <ul>
  <li>How could i further debug the problem</li>
  <li>How can i really delete/reset all user settings and files and cleanup the registry</li>
  <li>Could this be related to solutions or projects</li>
  <li>Any third party components known to be problematic? .Net Frameworks?</li>
  </ul>