title: Sigining UWP-Apps with custom code sign certificate
body: <p>What exactly is the requirement to create a company internal App with Xamarin.Forms UWP? I can compile the *.appxbundle-Package but nobody can install it because of an certificate error. If I try to use our normal code signing certificate from StartSSL to sign the package, I got the following error:</p>
  
  <blockquote>
    <p>The Manifest Designer could not import the certificate.</p>
    
    <p>The certificate you selected is not valid for signing because it is
    either expired or has another issue. For more information, see:
    <a href="https://go.microsoft.com/fwlink/?LinkID=241478" rel="nofollow noreferrer">https://go.microsoft.com/fwlink/?LinkID=241478</a></p>
  </blockquote>
  
  <p>The same certificate is used by our other desktop application with the signtool, so I guess the certificate is ok. Usage of the signtool for other .NET assemblies such as WPF projects:</p>
  
  <pre><code>"C:\Program Files (x86)\Windows Kits\10\bin\x86\signtool.exe" sign /f "..\..\..\..\..\Finaltec\Framework\Signing.pfx" /p ... /tr "http://timestamp.globalsign.com/scripts/timestamp.dll" "$(TargetPath)"
  </code></pre>
  
  <p>Are there any special requirements to sign a UWP app so anyone can install it? The used certificate is a Class 3 StartSSL Code Signing Certificate and it is valid until Junuary 2020. If I try to install the app with the generated test certificate from the Visual Studio, I got the message that the root certificate is not trusted and the installation process will be canceled. Even if I install the certificate manual before I got the same result error.</p>
  
  <p><strong>Code Signing Certificate informations:</strong> </p>
  
  <ul>
  <li>Name: CVA Computer - Visualisierung und Animation GmbH</li>
  <li>Address: Beckebohnen 2</li>
  <li>Zip, City: 31618 Liebenau</li>
  <li>State, Country: Niedersachsen, DE</li>
  <li>Phone: +49-502398110</li>
  <li>Email:  info@cva.de</li>
  <li>Expiry Date: 2017-04-14</li>
  </ul>
  
  <p><strong>Package.appxmanifest content:</strong></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;Package xmlns="http://schemas.microsoft.com/appx/manifest/foundation/windows10" xmlns:mp="http://schemas.microsoft.com/appx/2014/phone/manifest" xmlns:uap="http://schemas.microsoft.com/appx/manifest/uap/windows10" IgnorableNamespaces="uap mp"&gt;
    &lt;Identity Name="f736c883-f105-4d30-a719-4bf328872f5e" Publisher="CN=CVA Computer - Visualisierung und Animation GmbH" Version="1.0.1.0" /&gt;
    &lt;mp:PhoneIdentity PhoneProductId="f736c883-f105-4d30-a719-4bf328872f5e" PhonePublisherId="00000000-0000-0000-0000-000000000000" /&gt;
    &lt;Properties&gt;
      &lt;DisplayName&gt;CVA.COS_App&lt;/DisplayName&gt;
      &lt;PublisherDisplayName&gt;CVA Computer - Visualisierung und Animation GmbH&lt;/PublisherDisplayName&gt;
      &lt;Logo&gt;Assets\StoreLogo.png&lt;/Logo&gt;
    &lt;/Properties&gt;
    &lt;Dependencies&gt;
      &lt;TargetDeviceFamily Name="Windows.Universal" MinVersion="10.0.0.0" MaxVersionTested="10.0.0.0" /&gt;
    &lt;/Dependencies&gt;
    &lt;Resources&gt;
      &lt;Resource Language="x-generate" /&gt;
    &lt;/Resources&gt;
    &lt;Applications&gt;
      &lt;Application Id="App" Executable="$targetnametoken$.exe" EntryPoint="FPCL.WIndows.App"&gt;
        &lt;uap:VisualElements DisplayName="CVA.COS_App" Square150x150Logo="Assets\Square150x150Logo.png" Square44x44Logo="Assets\Square44x44Logo.png" Description="CVA.COS_App" BackgroundColor="#f4f4f4"&gt;
          &lt;uap:DefaultTile Wide310x150Logo="Assets\Wide310x150Logo.png"&gt;
          &lt;/uap:DefaultTile&gt;
          &lt;uap:SplashScreen Image="Assets\SplashScreen.png" /&gt;
          &lt;uap:InitialRotationPreference&gt;
            &lt;uap:Rotation Preference="portrait" /&gt;
            &lt;uap:Rotation Preference="landscape" /&gt;
            &lt;uap:Rotation Preference="portraitFlipped" /&gt;
            &lt;uap:Rotation Preference="landscapeFlipped" /&gt;
          &lt;/uap:InitialRotationPreference&gt;
        &lt;/uap:VisualElements&gt;
      &lt;/Application&gt;
    &lt;/Applications&gt;
    &lt;Capabilities&gt;
      &lt;Capability Name="internetClient" /&gt;
      &lt;Capability Name="privateNetworkClientServer" /&gt;
      &lt;DeviceCapability Name="webcam" /&gt;
    &lt;/Capabilities&gt;
  &lt;/Package&gt;
  </code></pre>