title: How to install an older version of scala
body: <p>I currently had installed <code>scala 2.11.7</code> but in order to fix <a href="https://stackoverflow.com/questions/29339005/run-main-0-java-lang-nosuchmethoderror-scala-collection-immutable-hashset-emp">this issue</a>, I have to install a older version of scala(<code>2.10.5</code>). When I try to install with brew, I keep getting the following error</p>
  
  <pre><code>Error: No available formula for 2.10.5 
  </code></pre>
  
  <p>I tried downloading the binaries for scala download page but when I load the SDK and all the libraries in <code>IntelliJ</code>, I just get this error </p>
  
  <pre><code>Error:scalac: No 'scala-library*.jar' in Scala compiler classpath in Scala SDK scala-sdk-2.10.5
  </code></pre>
  
  <p>So what is the right way to install an older version of scala and setting the same in intellij</p>