title: Unable to step into 3rd party code using debugger
body: <p>I want to step into the DevExpress XAF code using the debugger.</p>
  
  <p>I have <a href="https://www.devexpress.com/Support/Center/Question/Details/T812275/can-i-set-up-pdb-debugging-for-nuget-packages" rel="nofollow noreferrer">asked about it here</a> but am having problems spotting what I have done wrong.</p>
  
  <p>VS2019 16.2.2
  Dev Express XAF 19.1.5 Winforms project
  The break point is in Program.cs
  at</p>
  
  <pre><code>winApplication.Start
  </code></pre>
  
  <p>which is in </p>
  
  <pre><code>DevExpress.ExpressApp.Win.WinApplication
  </code></pre>
  
  <p>I downloaded the .pdb files and set up the Symbols
  <a href="https://i.stack.imgur.com/SviVn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SviVn.png" alt="Symbols set up"></a></p>
  
  <p>I un-checked Tools->Options->Debugging->Enable Just My Code</p>
  
  <p>At the breakpoint Debug->Windows->Modules shows that the Symbol file for mscorlib.dll is loaded.</p>
  
  <p><a href="https://i.stack.imgur.com/6Ubtx.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6Ubtx.png" alt="mscorelib"></a></p>
  
  <p>Exception settings are </p>
  
  <p><a href="https://i.stack.imgur.com/bMmOj.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bMmOj.png" alt="Exception settings"></a></p>
  
  <p>[Update]</p>
  
  <p>Lance Li pointed out the cannot find or open the pdb file message
  <a href="https://i.stack.imgur.com/VnVoL.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/VnVoL.png" alt="cannot find or open the pdb file"></a></p>
  
  <p>When I select Symbol Load Information it mentions the location is </p>
  
  <pre><code>C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\DevExpress.Utils.v19.1\v4.0_19.1.5.0__b88d1754d700e49a\DevExpress.Utils.v19.1.pdb: Cannot find or open the PDB file.
  </code></pre>
  
  <p>I tried clicking the load all symbols button in the symbols screen but it did not help.</p>
  
  <p>I attempted to locate the pdb but got a message</p>
  
  <blockquote>
    <p>A matching symbol file was not found in this folder</p>
  </blockquote>
  
  <p><a href="https://i.stack.imgur.com/HJa7X.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HJa7X.png" alt="matching symbol file not found"></a></p>
  
  <p>I tried suspending Resharper and that did not help.</p>
  
  <p>[Update]</p>
  
  <p>I noticed that it is looking for the file in the GAC</p>
  
  <blockquote>
    <p><a href="https://i.stack.imgur.com/ffiaZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ffiaZ.png" alt="In the GAC"></a></p>
  </blockquote>
  
  <p>I see that there is a copy of mscorlib.pdb in d:\pdb\19.1
  Could it be that that somehow re-arranges something to expect to find the Dev Express .pdbs in the GAC?</p>
  
  <p>The source code is on <a href="https://github.com/kgreed/SO57829980" rel="nofollow noreferrer">GitHub</a></p>
  
  <p>[Update]</p>
  
  <p>In the DevExpress question Dennis points out that when he hits F11 Visual Studio asks for a source code path.  I think this happened once for me I have selected the default path. Now Visual Studio no longer asks. </p>
  
  <p>I tried re-cloning the application but it did not help.
  I tried opening up with VS2017 but that did not help.</p>
  
  <p>[Update]</p>
  
  <p>I installed on to a different computer
  then at the break point I received a dialog box to select the source code.</p>
  
  <p>I located the source at </p>
  
  <pre><code>Directory of C:\Program Files (x86)\DevExpress 19.1\Components\Sources\DevExpress.ExpressApp\DevExpress.ExpressApp\DevExpress.Persistent.Base
  </code></pre>
  
  <p>Then I was able to step through the Dev Express code on the second computer.</p>
  
  <p>Now to figure out how to correct the behaviour on the first computer.</p>
  
  <p>[Update]
  I was able to get the Find Source dialog up by the following method.
  Run to the break point , then select Debug -> Windows -> Modules.
  Then right click an unloaded module and un-check Always Load Automatically.</p>
  
  <p>After that when I ran again I got the dialog allowing me to locate the source.</p>