title: VS 2015: C# NuGet Package restore failed. The file or directory is corrupted and unreadable
body: <p>I have a Visual Studio 2015 C# project consuming packages from NuGet. The solution contains several C# projects and is checked out on drive C.</p>
  
  <p><strong><em>Problem</em></strong>: I cannot compile the solution or restore nuget packages since several hours. I get the following error:</p>
  
  <blockquote>
    <p>NuGet Package restore failed for project ...: The file or directory is
    corrupted and unreadable.</p>
  </blockquote>
  
  <p>The <strong>Package Manager Console</strong> reports the following error after startup:</p>
  
  <blockquote>
    <p>The file or directory is corrupted and unreadable.</p>
  </blockquote>
  
  <p>Restarting Visual Studio does not fix the issue. Accessing the files with File Explorer and Notepad++ works. I don't experience any internet connectivity issues. <a href="https://status.nuget.org/" rel="nofollow noreferrer">Nuget</a> seems to be online.</p>
  
  <p>There is no private nuget registry in use, the  default package source <code>https://api.nuget.org/v3/index.json</code> is used.</p>
  
  <p>Visual Studio 2015 Professional 14.0.25431.01 Update 3
  Package Manager Console Host Version 3.6.0.2511</p>