title: TFS / Visual Studio 2015 does not trigger a pending add action for added files
body: <p>Since a couple of weeks we've been having strange issues happening within our TFS instance.</p>
  
  <p>for some unknown reason whenever we try to add a new or existing file to a solution / project, visual studio only detects a change in the project file to add the reference to the newly added file but ignores the "physical" file itself. </p>
  
  <p>In the pending changes we only see a change on the *.proj file and that's it.</p>
  
  <p>It looks like this:</p>
  
  <p><a href="https://i.stack.imgur.com/URtsj.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/URtsj.png" alt="Adding a new file"></a></p>
  
  <p><a href="https://i.stack.imgur.com/G0H14.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/G0H14.png" alt="added view"></a></p>
  
  <p><a href="https://i.stack.imgur.com/xJBQQ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xJBQQ.png" alt="check-out warning on project file"></a></p>
  
  <p><a href="https://i.stack.imgur.com/MnCkh.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MnCkh.png" alt="solution explorer after the add"></a></p>
  
  <p><a href="https://i.stack.imgur.com/61cql.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/61cql.png" alt="Team Explorer - Pending Changes after the add"></a></p>
  
  <p><em>(i know the screenshots are different projects, but when i was recreating the error for the images it suddenly went alright in the first project so i tried another).</em></p>
  
  <p>The file does not appear in the excluded list nor does it appear in the detected changes.</p>
  
  <p>From what i've found online is that it could be a binding issue. So things i tried are the following:</p>
  
  <ul>
  <li>Deleting and creating a new local workspace</li>
  <li>unbinding the solution and every project, Check this in, add the binding again and lastly checking this change again back in.</li>
  </ul>
  
  <p>The issue occurs on existing projects which have been under source control for atleast a week or more.</p>
  
  <p>The issue occurs at multiple developers / machines and I don't seem to be able to find a correlation on when this happens. Sometimes when I add a file my colleague can not add it then some other time it does not work for both of us. Another scenario is that projects work perfectly fine one day then another day they don't</p>
  
  <p>We have tried this on similar and different projects in TFS. A Workaround is available by manually adding the missing files by interface or cmdprompt but it worked before and it easy to miss a file because of this.</p>
  
  <p>We are running TFS Server 2015 onprem on a Windows Server 2012 R2 using the default SQLExpress instance it came with. Our Visual Studio edition is 2015 Community Edition with SQL Server tools enabled on them (latest stable release).</p>
  
  <p>Edit: This might be something but can also be nothing. When attempting another file just ago I had the Team Explorer open and I saw the added file in the pending changes and it suddenly disappeared changing to the state i describe in this post.</p>
  
  <p>Hoping someone has a suggestion to find the cause and a solution for this issue.</p>