title: Xamarin proguard.ParseException: Unknown option '' in line 1 of file 'Properties/proguard.cfg'
body: <p>I'm trying to use proguard with Xamarin.
  So I enabled it in project options (checked <code>Enable ProGuard</code>), and I created a file <code>proguard.cfg</code> in Properties, (as new Text file, is it right?)
  and checked the BuildAction -> ProguardConfiguration</p>
  
  <p><a href="https://i.stack.imgur.com/4nPXZ.png" rel="noreferrer"><img src="https://i.stack.imgur.com/4nPXZ.png" alt="Proguard file config"></a></p>
  
  <p>The proguard file contains only a -keep configuration, with a comment. Whether I leave or remove the comment, I always get a parse error on line 1 :</p>
  
  <pre><code># test comment 
  -keep class !android.support.v7.view.menu.**, !android.support.design.internal.NavigationMenu, !android.support.design.internal.NavigationMenuPresenter, !android.support.design.internal.NavigationSubMenu, android.support.** {*;}
  </code></pre>
  
  <p>I get a <code>Unknown option '﻿' in line 1</code> error.</p>
  
  <blockquote>
    <p>/Library/Frameworks/Mono.framework/External/xbuild/Xamarin/Android/Xamarin.Android.Common.targets:
    Error: Tool exited with code: 1. Output: proguard.ParseException:
    Unknown option '﻿' in line 1 of file 'Properties/proguard.cfg'<br>
    included from argument number 10  at
    proguard.ConfigurationParser.parse(ConfigurationParser.java:191)  at
    proguard.ProGuard.main(ProGuard.java:484)  (WheezMe.Droid)</p>
  </blockquote>
  
  <p>Any idea ?</p>