need to generate invalid response

Hello
The web server i'm working on is W2k8, IIS7,  ASP.NET.
Our organization uses Apache as proxy server. It passes requests from the Internet to IIS7 and then the response from IIS7 back to the clients.
Sometimes Apache returns error 502(Bad Gateway) to the clients. It means that the response from IIS was invalid. To locate the cause of the problem I need to generate an invalid response on purpose.
How can I accomplish this with ASP.NET?


Thanks

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