title: How to Migrate TFS Collection from TFS-2012 Express to TFS-2013 Server When Still Attached to Uninstalled Service?
body: <p>Everything worked fine until I attempted to attach the old <em>tfs_default_collection</em> database (restored to SQL Server 2012 Developer as the new database <em>tfs_collection_2012</em>), when I get the error below:</p>
  
  <p><img src="https://i.stack.imgur.com/0Gc4R.png" alt="enter image description here"></p>
  
  <p>As per the very first instruction of the TFS 2013 Setup process, I fully uninstalled TFS 2012 Express several hours ago when I bean the migration. Is there any way to properly detach this Collection with TFS-2013 now properly installed and otherwise working, so that it can be attached  to TFS-2013 for migration/update?</p>
  
  <p>I have checked all the privileges (in TFS and SQL Server) and believe those to be properly setup, though I am by no means a TFS Administrator.</p>
  
  <p>I still have the SQL Server backups of both <strong>Tfs_Configuration</strong> and <strong>Tfs_DefaultCollection</strong> from the old instance of <em>SQL Server 2012 Express</em> and <em>TFS-2012 Express</em>.</p>