title: Cannot step into .NET source code
body: <p>Environment: W10 Pro x64, Visual Studio Premium 2013 Update 5, Class Library project, target framework .NET 4.5.2.</p>
  
  <p>I am trying to step into the .NET source while debugging my code, but for the life of me I cannot get it to work - hitting <strong>F11/Step Into</strong> results in the debugger just going to the next line of my source.  I am trying to step into a call of <a href="https://msdn.microsoft.com/EN-US/library/de3dhzwy(v=VS.110,d=hv.2).aspx" rel="nofollow noreferrer"><code>Type.InvokeMember()</code></a>. In the <strong>Modules</strong> window, I see <code>mscorlib.dll</code> has its symbols loaded. One interesting bit of info; not sure if it's relevant or not: the <strong>Path</strong> of <code>mscorlib.dll</code> is shown as</p>
  
  <pre><code>C:\Windows\Microsoft.Net\assembly\GAC_32\mscorlib\v4.0_4.0.0.0__b77a5c561934e089\mscorlib.dll
  </code></pre>
  
  <p>but the <strong>Version</strong> column says</p>
  
  <pre><code>4.6.1637.0 built by: NETFXREL3STAGE
  </code></pre>
  
  <p>So <strong>question #1</strong>: is this bad?  (Also, here is the <strong>Symbol Load Information</strong> for <code>mscorlib.dll</code>):</p>
  
  <pre><code>C:\Program Files (x86)\Sage Software\Sage MAS 500 Client\PO\mscorlib.pdb: Cannot find or open the PDB file. 
  C:\Windows\Microsoft.Net\assembly\GAC_32\mscorlib\v4.0_4.0.0.0__b77a5c561934e089\mscorlib.pdb: Cannot find or open the PDB file. 
  C:\Windows\mscorlib.pdb: Cannot find or open the PDB file. 
  C:\Windows\symbols\dll\mscorlib.pdb: Cannot find or open the PDB file. 
  C:\Windows\dll\mscorlib.pdb: Cannot find or open the PDB file. 
  C:\Temp\SymbolCache\mscorlib.pdb\a41a5f0d874946f7af63753340e70f252\mscorlib.pdb: Cannot find or open the PDB file. 
  C:\Temp\SymbolCache\MicrosoftPublicSymbols\mscorlib.pdb\a41a5f0d874946f7af63753340e70f252\mscorlib.pdb: Cannot find or open the PDB file. 
  SYMSRV:  C:\Temp\SymbolCache\mscorlib.pdb\A41A5F0D874946F7AF63753340E70F252\mscorlib.pdb not found
  SYMSRV:  http://referencesource.microsoft.com/symbols/mscorlib.pdb/A41A5F0D874946F7AF63753340E70F252/mscorlib.pdb not found
  http://referencesource.microsoft.com/symbols: Symbols not found on symbol server. 
  SYMSRV:  mscorlib.pdb from http://msdl.microsoft.com/download/symbols: 133365 bytes 
  http://msdl.microsoft.com/download/symbols: Symbols downloaded from symbol server. 
  C:\Temp\SymbolCache\mscorlib.pdb\A41A5F0D874946F7AF63753340E70F252\mscorlib.pdb: Symbols loaded.
  </code></pre>
  
  <p><hr>Also, if I hit <strong>F12</strong> when my cursor is on the call to <code>InvokeMember()</code>, I get a new "Generated Source File" window with the name <code>Type [from metadata]</code> on the window tab. Mousing over the tab gives me the text</p>
  
  <pre><code>Preview of C:\Users\conrad\AppData\Local\Temp\6012$CommonLanguageRuntimeLibrary$v4.0.30319$NoDynamic\System.Type.cs [from metadata]
  </code></pre>
  
  <p>in the tooltip. There are 3 declarations of <code>InvokeMember</code>, for its 3 variants. The one with the most args is marked <code>abstract</code> (the version I am using), and the other 2 have the attributes</p>
  
  <pre><code>[DebuggerHidden]
  [DebuggerStepThrough]
  </code></pre>
  
  <p>So - <strong>question #2</strong> - are these attributes blocking me from stepping into the source? If so, is there a way to override?</p>
  
  <p>It feels like I have looked at about every other SO question on stepping into .NET source, but with no success - here are my Debug options:
  <a href="https://i.stack.imgur.com/mAtxc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mAtxc.png" alt="VS 2013 Debug Options"></a></p>
  
  <p>And my Symbol Locations:</p>
  
  <p><a href="https://i.stack.imgur.com/LhxSq.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LhxSq.png" alt="Symbol Locations"></a></p>