title: How do I target TFS build agents that does not have a specific tag?
body: <p>Our MS build setup has several build machines with multiple agents. The agents are tagged with different software installed on the build machines. My build is looking for two tags using "MatchAtLeast". Recently, TFS has occasionally picked another build machine, on which it always fails. I believe it might be because of a certain other software package that is installed on that particular machine, and so I would like to <em>exclude</em> any machine from the ones available for my build that has a specific tag representing the offending software.</p>
  
  <p>I guess I could add tags to everything that does not have that software, but that seems silly, and then if that ever do get installed, the person adding it would need to not just add a tag for the newly installed software, but also remove this other tag stating that it doesn't have that software.</p>
  
  <p>So is there a way to configure your build definition to <strong><em>avoid</em></strong> build agents with a certain tag?</p>
  
  <p>We are using TFS 2012 update 2.</p>