Redirect Snippet

<!-- Rewrite all qr-dev.2sxc.org/xyz to be handled by the redirect web service -->
<rule name="Forward shortlinks to redirect-system" stopProcessing="true" enabled="true">
  <!-- handle urls with 1 and 25 numbers/chars; adapt it as you need it -->
  <match url="^([A-Za-z0-9]{1,25})$" />
  <!-- we only want to capture urls on the shortdomain qr-dev.2sxc.org -->
 <conditions>
  <add input="{HTTP_HOST}" pattern="^(www\.)?qr-dev\.2sxc\.org$" ignoreCase="true" />
 </conditions>
 <!-- note that the root path can have subportal name in it - if the app is installed in a sub-portal -->
 <!-- note also that in DNN7, the root path (after the sub-portal) is not /api/2sxc but instead /desktopmodules/2sxc/api -->
 <action type="Rewrite" url="/api/2sxc/app/ShortLinks2/api/redirect/go?key={R:1}" />
</rule>

Assembly Snippet

Add this below "system.web" -> "compilation" -> "assemblies"

<!-- needed for shortlinks -->
<add assembly="System.Net.Http, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />