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I have a web app that allos users to upload files (using Telerik's RadAsyncUpload control).

My web.config file is set to allow files up to 2Gb and, when I run the app against Visual Studio's built-in web server it runs just fine.

However, if I switch to using IIS (I have IIS 7.5.7600.16385 installed on my machine) files above a certain size simply fails to upload.

I'm still working on identifying the exact upper limit, but I know a file of 60Mb or more won't upload.

My question is: is there anything specific in IIS that I should check/change?

Just to be clear, I have got the following in my web.config file...

<httpRuntime maxRequestLength="2097152" executionTimeout="86400"/>
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It seems that, in their infinite wisdom, MS engineers have decided to add a different key with a different unit of measure to chip in with this.

The following is from the <configuration><system.webServer> element of our modified web.config file...

            <!-- This value should be 1024 * maxRequestLength -->
            <requestLimits maxAllowedContentLength="1073741824" />

I'd be grateful to hear any comments that suggest I have this wrong, but, at least on the face of it, this seems to work.

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was this in addition to the previous web.config line, or instead of? Glad you appear to solved it for yourself – datatoo Jul 25 '12 at 14:47
As well as. The original value was an attribute of the <httpruntime> element. Is this a child of the <system.webServer> element – Stuart Hemming Jul 25 '12 at 18:23

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