can't reference class from another project of the same solution
<p>My solution contains several projects including <code>Commons</code> and <code>TerminatorConsole2</code>. Now I want to refer <code>Commons.Constants</code> class from <code>TerminatorConsole2.Utils.Constants</code> file:</p>

<pre><code>namespace TerminatorConsole2.Utils
{
    class Constants
    {
        public const string MANAGEMENT_CONSOLE_ADDRESS =
            Commons.Constants.USE_EXTRA_WCF_INSTANCE ?
                "net.pipe://localhost/xxx" :
                "net.pipe://localhost";
</code></pre>

<p>But I receive "Cannot resolve symbol" on "Commons".
Adding "using Commons" doesn't help, I receive same error.</p>

<p>Why one project can not use class from another project of the same solution?</p>

<p><strong>UPD</strong> Adding <code>Constants</code> class. However I already use it from one another project so I think this class is OK:</p>

<pre><code>namespace Commons
{

public class Constants
{
    public const int MAX_INSTRUMENTS_NUMBER_IN_SYSTEM = 200;
    public const bool USE_EXTRA_WCF_INSTANCE = true;
}

}
</code></pre>
