Auri's Blog

I had this issue after switching from an Azure app service to DiscountASP.net. I just had to add the following to the web.config to fix the IIS config:

<system.webServer> 
  <security>
    <requestFiltering>
      <filteringRules>
         <remove name="facebookexternalhit" />  
      </filteringRules>
    </requestFiltering>  
  </security>  
</system.webServer>

The first time I tried this it did not work. However, I emailed support and they explained THEY had to fix it “at the root.” So, for what it’s worth this does work, but in a shared hosting environment, you may need to put it in the server’s web.config, possibly replacing the rule name to what’s appropriate for your hosting provider.