Maximum request length exceeded exception - exception

Question

I'm trying to upload a 20 meg file using the upload control and it's working fine on visual studio's built in webserver but once I publish it to the production server (which I have no access to) I keep getting the following error :
Server Error in '/' Application.
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Maximum request length exceeded.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Web.HttpException: Maximum request length exceeded.
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
Stack Trace:
[HttpException (0x80004005): Maximum request length exceeded.]
System.Web.HttpRequest.GetEntireRawContent() [phone]
System.Web.HttpRequest.GetMultipartContent() +72
System.Web.HttpRequest.FillInFormCollection() +245
System.Web.HttpRequest.get_Form() +119
System.Web.HttpRequest.get_HasForm() [phone]
System.Web.UI.Page.GetCollectionBasedOnMethod(Boolean dontReturnNull) +124
System.Web.UI.Page.DeterminePostBackMode() +83
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +270
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I've added the following to my system.web node so i don't know what the real issue is.
<httpRuntime executionTimeout="800" maxRequestLength="51200" />
Any direction on this would be very helpful.

Answer 1

If config file change doesn't work, please try to update property httpRuntime executionTimeout="9200" maxRequestLength="200000"> directly from IIS.
For reference:

Answer 2

Although you have a 20Mb file, it is possible that encoding or other content on the page causes the 50Mb limit you have set to be exceeded. I recommend doubling your current setting.
There is also another web.config setting that could come into play: security request filtering maxAllowedContentLength.
This default to 30MB, but could be set differently in your environment.
The web.config entry would be something along the lines of:
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="1550000000" maxQueryString="16384" />
<fileExtensions>
<add fileExtension="." allowed="true" />
</fileExtensions>
</requestFiltering>
</security>