Hi Marc,

thanks for your reply.

This is my security.config:

<?xml version="1.0" encoding="utf-8"?>
<security>
  <!--Added v4.3.0 -->
  <cors>
    <whitelist>
      <!--
      Demo: Adding a url will send cors headers to that requesting url.
            "*" acts as a universal selector.
      -->
      <add url="http://imageprocessor.org"/>
    </whitelist>
  </cors>
  <services>
    <service name="LocalFileImageService" type="ImageProcessor.Web.Services.LocalFileImageService, ImageProcessor.Web"/>
    <!--Disable the LocalFileImageService and enable this one when using virtual paths. -->
    <!--<service name="CloudImageService" type="ImageProcessor.Web.Services.CloudImageService, ImageProcessor.Web">
      <settings>
        <setting key="MaxBytes" value="8194304"/>
        <setting key="Timeout" value="30000"/>
        <setting key="Host" value="http://yourhost.com/"/>
      </settings>
    </service>-->
    <service prefix="remote.axd" name="RemoteImageService" type="ImageProcessor.Web.Services.RemoteImageService, ImageProcessor.Web">
      <!-- The timeout for a request in milliseconds and the maximum 
            allowable download in bytes. -->
      <settings>
        <setting key="MaxBytes" value="4194304"/>
        <setting key="Timeout" value="3000"/>
        <!-- Added version 4.2.0. -->
        <setting key="Protocol" value="http"/>
        <!-- Added version 4.7.0. Optional -->
        <!-- Sets a useragent value for the request. Useful for social networks.
             See http://www.useragentstring.com/ for available values. -->
        <setting key="Useragent" value=""/>
      </settings>
      <!-- Sets allowable domains to process images from. -->
      <whitelist>
        <add url="https://betzold.de"/>
        <add url="https://static.betzold-educational.com"/>
        <add url="https://static.betzold.de"/>
        <add url="https://betzold-educational.com"/>
        <add url="https://static.betzold-educational.com"/>
        <add url="https://rasquin.net"/>
      </whitelist>
    </service>
    <!-- Add other service implemtations here. -->
  </services>
</security>

As you can see above, I have added several whitelist domains.

This is my test code:

<table>
    <tr>
        <td style="border: 1px solid #ccc">
            <h4>code4.it</h4>
            <img src="https://code4.it/img/Betzold-100er-Rechenbox-87275_MSTR-L.jpg?mode=boxpad&width=100&height=200" />
            <br />
        </td>
        <td style="border: 1px solid #ccc">
            <h4>static.betzold-educational.com</h4>
            <img src="https://static.betzold-educational.com/images/prod/87275/Betzold-100er-Rechenbox-87275_MSTR-L.jpg?mode=boxpad&width=100&height=200" />
            <br />
        </td>
        <td style="border: 1px solid #ccc">
            <h4>rasquin.net</h4>
            <img src="https://rasquin.net/img/Betzold-100er-Rechenbox-87275_MSTR-L.jpg?mode=boxpad&width=100&height=200" />
        </td>
    </tr>
</table>

Same Image on three drifferent servers. Here is the result

https://code4.it/ is the only domain under which the image processing works. Even though it has not been added to the whitelist.

Are there any serverside restrictions that could prevent the images beeing processed?

I'm on my test environment on my local maschine but have set up a test domain on IIS : https://campusshop.localtest.me/ pointing to 127.0.0.1 so I can run the site under https

Hi Marc,

yes the first option works:

/remote.axd/your-external-image?width=300

Thank you so much for helping me out!

Have a nice day