title: Android SDK not found error
body: <p>I was working on an Android Project that uses Facebook SDK. Everything was fine until today. When I tried to run the project it gives the following error.</p>
  
  <pre><code>Unable to resolve target 'android-10' until the SDK is loaded
  </code></pre>
  
  <p>Although I have SDK 2.3.3 (Level 10), it doesn't appear in the project properties. In properties of Eclipse it says, </p>
  
  <pre><code>This Android SDK requires Android Developer Toolkit version 21.1.0 or above.  Current version is 21.0.0.2012-10-31-0-17.  Please update ADT to the latest version.
  </code></pre>
  
  <p>However, according to Android SDK Manager, I already installed the latest version (see image below).</p>
  
  <p><img src="https://i.stack.imgur.com/B8GlI.png" alt="enter image description here"></p>
  
  <p>How can I resolve the problem? Any help would be appreciated, thanks in advance.</p>
  
  <p><strong>Edit:</strong></p>
  
  <p>I'm using Mac OSX 10.8, and I tried restarting both eclipse and os.</p>