I'm trying to upload files in ASP.Net with the ajax uploader. The files can be up to 20MB so I've set the maxsizekb to 20240.

I also followed this blogpost: http://weblogs.asp.net/jgalloway/archive/2008/01/08/large-file-uploads-in-asp-net.aspx 

to change my allowed file size in my web.config.

Placed this in System.Webserver:

<security>

      <requestFiltering>

        <requestLimits maxAllowedContentLength="52428800" /> <!--50MB-->

      </requestFiltering>

    </security>

And this in httpruntime:

executionTimeout="220" maxRequestLength="52428800" 

Now my problem is that all my files above 300kb fail to upload.  Everything below 300kb works fine. What could be the problem? 

I also tried this with no luck:

<add key="CuteWebUI.AjaxUploader.RewritePath" value="IIS7" />

<add key="CuteWebUI.AjaxUploader.UseAspNetStream" value="True" />