title: Class inaccessible due to its protection level
body: <p>I have one project IBSampleApp used in two solutions and it’s classes suffer the following compiler error in both.</p>
  
  <blockquote>
    <p>inaccessible due to it’s protection level</p>
  </blockquote>
  
  <p>Error in IBClient.cs of IB Execution project in Execution solution:</p>
  
  <p><a href="https://i.stack.imgur.com/fk0bt.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/fk0bt.png" alt="enter image description here"></a></p>
  
  <p>TickPriceMessage class in IBSampleApp project:</p>
  
  <p><a href="https://i.stack.imgur.com/pkblo.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/pkblo.png" alt="enter image description here"></a></p>
  
  <p>Added InternalsVisibleTo property to AssemblyInfo.cs of IBSampleApp project (recommended by @JamesFaix):</p>
  
  <p><a href="https://i.stack.imgur.com/U519I.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/U519I.png" alt="enter image description here"></a></p>
  
  <p>The problem persistes still. How to make TickPriceMessage class available to both solutions?</p>