I had a bit of trouble getting the upload control to work but managed to get it going in development using the http module and handler for IIS6 specified in the infragistics developers guide: http://help.infragistics.com/Help/NetAdvantage/jQuery/2011.2/CLR4.0/html/igUpload_Using_HTTP_Handler_and_Modules.html.

Everything was working fine on my local development pc.

Now that I'm pushing up to our testing platform, which runs IIS7, I again followed the instructions in that link, removing the IIS6 tags and replacing them with the suggested IIS7 tags.  Now I keep getting this error:

nosuchfilekeyid: The file you requested could not be found. Probably this file is too big.

My Web.config contains the following:

<appSettings>
   <add key="fileUploadPath" value="~/App_Data/Temp" />
   <add key="maxFileSizeLimit" value="100000000" />
</appSettings>

 <system.webServer>
    <modules runAllManagedModulesForAllRequests="true">        

    <add name="IGUploadModule" type="Infragistics.Web.Mvc.UploadModule" preCondition="managedHandler" />

    </modules>

    <handlers>

        <add name="IGUploadStatusHandler" path="IGUploadStatusHandler.ashx" verb="*" type="Infragistics.Web.Mvc.UploadStatusHandler" preCondition="integratedMode" />

    </handlers>

</system.webServer>