title: php: how to install a package using composer
body: <p>I'm totally new to composer ;-)</p>
  
  <p>I try to install mPDF 7.1 on my localhost (ubuntu 16.04) with composer.</p>
  
  <p>1.) I installed composer 1.6.5.</p>
  
  <p>2.) Downloaded mPDF 7.1 (<a href="https://github.com/mpdf/mpdf/releases" rel="nofollow noreferrer">https://github.com/mpdf/mpdf/releases</a>) and unzipped folder to hdd.</p>
  
  <p>3.) Open terminal in mpdf-7.1.0 folder and typed <code>$ composer require mpdf/mpdf</code> to start process</p>
  
  <p>--> Error message is thrown:</p>
  
  <pre><code>Problem 1
      - The requested package mpdf/mpdf No version set (parsed as 1.0.0) is satisfiable by mpdf/mpdf[No version set (parsed as 1.0.0)] but these conflict with your requirements or minimum-stability.
  </code></pre>
  
  <p>So I don't know what's the problem is and don't find any help searching the web. Can you help me?</p>
  
  <p>Andreas</p>
  
  <p><strong>EDIT</strong>: I tried also: </p>
  
  <p><code>$ composer require mpdf/mpdf:7.1.0</code> and</p>
  
  <p><code>$ composer require mpdf/mpdf "^7.1.0"</code></p>
  
  <p>throw same error message...</p>