How can I run Orthanc behind Microsoft IIS?

Similarly to Apache and nginx, Orthanc can run behind Microsoft IIS (Internet Information Services) servers through reverse proxying. The instructions below are provided courtesy of Mark Hodge. They also illustrate how to configure HTTPS encryption.

  • IIS is available as a feature you can enable via the Programs and Features in non Server versions of Windows.

  • Add Application Request Routing 3.0.

  • Add URL Rewrite module 2.

  • In IIS Manager bind an SSL certificate to port 443 on the default web site being used for Orthanc.

  • Add the following web.config at the root of the default website:

<?xml version="1.0" encoding="UTF-8"?>
        <clear />
        <rule name="HTTP to HTTPS redirect" stopProcessing="true">
          <match url="(.*)" />
          <conditions logicalGrouping="MatchAll" trackAllCaptures="false">
            <add input="{HTTPS}" pattern="off" ignoreCase="true" />
          <action type="Redirect" url="https://{HTTP_HOST}/{R:1}" redirectType="Found" />
        <rule name="ReverseProxyInboundRule1" stopProcessing="true">
          <match url="(.*)" />
          <conditions logicalGrouping="MatchAll" trackAllCaptures="false" />
          <action type="Rewrite" url="{R:1}" />
  • In IIS Manager Open Application Request Routing Cache click on Server Proxy Settings on the right side of the window, change the Time-out to a much higher value. eg., 3600 = 1 hour to ensure download of DICOMDIR or ZIP’s doesn’t time out.

  • To allow user authentication against an Active Directory group add the following directly after <configuration> in the above web.config, grant the appropriate Active Directory group read permission on the wwwroot folder:

    <authentication mode="Windows" />
  • You also need to make sure registered users is empty in the Orthanc Configuration.json file:

"RegisteredUsers" : {  },