AjaxControlToolkit AjaxFileUpload can't upload IIS Reserved File Types

Question

I am writing/ have written a file upload portal for my company that requires the ability to upload a ton of different file types of various sizes and quantities. I used the AJaxControlToolkit AjaxFileUpload control.

The upload works well except when we upload what seems like IIS reserved file types. We can upload images, entire non-zipped folders, office docs etc.

When I try to upload the reserved file type the Firefox developer tools returns a server error, 'File Extension Not Allowed' error. This happens with .exe files and the one we need .stl files(in our case these are for 3d printing).

We have played with config files, Handler Mappings, HTTP response headers, MIME type configurations, and request filtering on the IIS manager at the app level, site level and server level and none seem to work.

The last bit of info is that zipping the file seems to get it through but we'd like to avoid asking the customer to do that.

IIS 8.5, C# .Net, Windows Server 2012 R2

I can post code if you need it but I am pretty sure it is a server configuration we need to change

Thanks for your help.

Walt

Edit: Below is my Config with the Fix included. this was an issue with white listed file types by the control and not the server. Thank you

<?xml version="1.0"?>
<configuration>
  <configSections>
    <section name="ajaxControlToolkit" type="AjaxControlToolkit.AjaxControlToolkitConfigSection, AjaxControlToolkit" requirePermission="false"/>
  </configSections>
  <appSettings/>
  <ajaxControlToolkit additionalUploadFileExtensions="bmp,stl"></ajaxControlToolkit>
  <system.webServer>
    <handlers>
      <add name="aa2" verb="*" path="AjaxFileUploadHandler.axd" type="AjaxControlToolkit.AjaxFileUploadHandler, AjaxControlToolkit"/>
    </handlers>  
  </system.webServer>
  <system.web>
    <compilation debug="true">
      <assemblies>
        <add assembly="System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add assembly="System.ServiceModel.Activation, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add assembly="System.Runtime.Serialization, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Web.ApplicationServices, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add assembly="System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
        <add assembly="System.Configuration, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
        <add assembly="System.ServiceModel, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Xml, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Web.Services, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
        <add assembly="System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Data.Linq, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Drawing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
        <add assembly="System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Data.Services.Client, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Data.Services.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Data.Entity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        <add assembly="System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
      </assemblies>
    </compilation>
    <pages>
      <controls>
        <add tagPrefix="ajaxToolkit" assembly="AjaxControlToolkit" namespace="AjaxControlToolkit"/>
      </controls>
    </pages>
  </system.web>
</configuration>

Answer 1

You need to add the additionalUploadFileExtensions attribute to ajaxControlToolkit section in Web.config:

<ajaxControlToolkit additionalUploadFileExtensions="exe,stl" />

Please refer to this article: https://github.com/DevExpress/AjaxControlToolkit/wiki/AjaxFileUpload-setup