title: How do I Setup an Agent Requirement in TeamCity that detects if an Application is installed?
body: <p>I have a build environment with multiple agents.<br>
  I would like to set up an Agent Requirement in my build that detects if certain software is installed.   In some cases I can look in the env.Path for a particular string.  But some software doesn't modify the Path.</p>
  
  <p>I realize that after I install the software i could edit the BuildAgent.properties file to set a particular property, but I'd like it to be more automatic.</p>
  
  <p>The specific instance is I have a build that uses MSDeploy to deploy websites, but it won't work if MSDeploy isn't installed. How can I specify in my build that I need an Agent that has MSDeploy installed? </p>