In web.config file in HTTPUpload site do the following settings. 


    <?xml version="1.0"?>
    <configuration xmlns="http://schemas.microsoft.com/.NetConfiguration/v2.0">         
      <system.web>
        <!-- This value is in **kilobytes** -->
        <!-- 512000 kilobytes = 500MB -->
        <httpRuntime executionTimeout="1200" maxRequestLength="512000" useFullyQualifiedRedirectUrl="false" minFreeThreads="8" minLocalRequestFreeThreads="4" appRequestQueueLimit="100"/>
      </system.web>

      <system.webServer>
        <security>
          <requestFiltering>
            <!-- This is the value in **bytes** -->
            <!-- 524288000 bytes = 500MB -->
            <!-- The maximum for this is 4,294,967,295 (3.99GB) - http://stackoverflow.com/questions/4022434/-->
            <requestLimits maxAllowedContentLength="524288000" />
          </requestFiltering>
        </security>
      </system.webServer>    
    </configuration>

Hope this will help.