title: Visual Studio 2017 doesn't start, but produces a process
body: <p>I'm using Visual Studio 2017 professional. Recently, something broke.
  When try to run it, it launches only once in about four trials. However, even if it doesn't launch, it produces a <code>devenv.exe</code> process that can be seen in task manager.
  Does dummy processes (each successful run of VS produces a few o them), are problematic to kill simultaneously, and cause problem while I try to install some extensions.</p>
  
  <p>I've tried deleting <code>%LocalAppData%\Microsoft\VisualStudio\15.0_5a56ecad\privateregistry.user.bin</code> (I found this solution somewhere, but I can't find it now). This seemed to help, but only temporarily (after some time, problem appeared again). And it also corrupts one of my extensions, which seems to depend on this file.</p>
  
  <p>Using Windows 7.</p>